diff options
Diffstat (limited to 'vendor/golang.org/x/tools/go/packages')
| -rw-r--r-- | vendor/golang.org/x/tools/go/packages/doc.go | 269 | ||||
| -rw-r--r-- | vendor/golang.org/x/tools/go/packages/external.go | 68 | ||||
| -rw-r--r-- | vendor/golang.org/x/tools/go/packages/golist.go | 337 | ||||
| -rw-r--r-- | vendor/golang.org/x/tools/go/packages/golist_fallback.go | 282 | ||||
| -rw-r--r-- | vendor/golang.org/x/tools/go/packages/packages.go | 824 |
5 files changed, 1780 insertions, 0 deletions
diff --git a/vendor/golang.org/x/tools/go/packages/doc.go b/vendor/golang.org/x/tools/go/packages/doc.go new file mode 100644 index 00000000..4f5a1a14 --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/doc.go @@ -0,0 +1,269 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +/* +Package packages loads Go packages for inspection and analysis. + +NOTE: THIS PACKAGE IS NOT YET READY FOR WIDESPREAD USE: + - The interface is still being revised and is likely to change. + - The implementation depends on the Go 1.11 go command. + - We intend to finalize the API before Go 1.11 is released. + +The Load function takes as input a list of patterns and return a list of Package +structs describing individual packages matched by those patterns. +The LoadMode controls the amounts of detail about the loaded packages. + +The patterns are used as arguments to the underlying build tool, +such as the go command or Bazel, and are interpreted according to +that tool's conventions. + +The Package struct provides basic information about the package, including + + - ID, a unique identifier for the package in the returned set; + - GoFiles, the names of the package's Go source files; + - Imports, a map from source import strings to the Packages they name; + - Types, the type information for the package's exported symbols; + - Syntax, the parsed syntax trees for the package's source code; and + - TypeInfo, the result of a complete type-check of the package syntax trees. + +(See the documentation for type Package for the complete list of fields +and more detailed descriptions.) + +For example, + + Load(nil, "bytes", "unicode...") + +returns four Package structs describing the standard library packages +bytes, unicode, unicode/utf16, and unicode/utf8. Note that one pattern +can match multiple packages and that a package might be matched by +multiple patterns: in general it is not possible to determine which +packages correspond to which patterns. + +Note that the list returned by Load (LoadAllSyntax in this case) +only contains the packages matched by the patterns. Their dependencies +can be found by walking the import graph using the Imports fields. + +The Load function can be configured by passing a non-nil Config struct as +the first argument. If you pass nil for the Config Load will +run in LoadAllSyntax mode, collecting the maximal amount of information +it can. +See the documentation for type Config for details. + +As noted earlier, the Config.Mode controls increasing amounts of detail +about the loaded packages, with each mode returning all the data of the +previous mode with some extra added. See the documentation for type LoadMode +for details. + +Most tools should pass their command-line arguments (after any flags) +uninterpreted to the loader, so that the loader can interpret them +according to the conventions of the underlying build system. +For example, this program prints the names of the source files +for each package listed on the command line: + + package main + + import ( + "flag" + "fmt" + "log" + + "golang.org/x/tools/go/packages" + ) + + func main() { + flag.Parse() + pkgs, err := packages.Load(nil, flag.Args()...) + if err != nil { + log.Fatal(err) + } + for _, pkg := range pkgs { + fmt.Print(pkg.ID, pkg.GoFiles) + } + } +*/ +package packages // import "golang.org/x/tools/go/packages" + +/* + +Motivation and design considerations + +The new package's design solves problems addressed by two existing +packages: go/build, which locates and describes packages, and +golang.org/x/tools/go/loader, which loads, parses and type-checks them. +The go/build.Package structure encodes too much of the 'go build' way +of organizing projects, leaving us in need of a data type that describes a +package of Go source code independent of the underlying build system. +We wanted something that works equally well with go build and vgo, and +also other build systems such as Bazel and Blaze, making it possible to +construct analysis tools that work in all these environments. +Tools such as errcheck and staticcheck were essentially unavailable to +the Go community at Google, and some of Google's internal tools for Go +are unavailable externally. +This new package provides a uniform way to obtain package metadata by +querying each of these build systems, optionally supporting their +preferred command-line notations for packages, so that tools integrate +neatly with users' build environments. The Metadata query function +executes an external query tool appropriate to the current workspace. + +Loading packages always returns the complete import graph "all the way down", +even if all you want is information about a single package, because the query +mechanisms of all the build systems we currently support ({go,vgo} list, and +blaze/bazel aspect-based query) cannot provide detailed information +about one package without visiting all its dependencies too, so there is +no additional asymptotic cost to providing transitive information. +(This property might not be true of a hypothetical 5th build system.) + +This package provides no parse-but-don't-typecheck operation because most tools +that need only untyped syntax (such as gofmt, goimports, and golint) +seem not to care about any files other than the ones they are directly +instructed to look at. Also, it is trivial for a client to supplement +this functionality on top of a Metadata query. + +In calls to TypeCheck, all initial packages, and any package that +transitively depends on one of them, must be loaded from source. +Consider A->B->C->D->E: if A,C are initial, A,B,C must be loaded from +source; D may be loaded from export data, and E may not be loaded at all +(though it's possible that D's export data mentions it, so a +types.Package may be created for it and exposed.) + +The old loader had a feature to suppress type-checking of function +bodies on a per-package basis, primarily intended to reduce the work of +obtaining type information for imported packages. Now that imports are +satisfied by export data, the optimization no longer seems necessary. + +Despite some early attempts, the old loader did not exploit export data, +instead always using the equivalent of WholeProgram mode. This was due +to the complexity of mixing source and export data packages (now +resolved by the upward traversal mentioned above), and because export data +files were nearly always missing or stale. Now that 'go build' supports +caching, all the underlying build systems can guarantee to produce +export data in a reasonable (amortized) time. + +Test "main" packages synthesized by the build system are now reported as +first-class packages, avoiding the need for clients (such as go/ssa) to +reinvent this generation logic. + +One way in which go/packages is simpler than the old loader is in its +treatment of in-package tests. In-package tests are packages that +consist of all the files of the library under test, plus the test files. +The old loader constructed in-package tests by a two-phase process of +mutation called "augmentation": first it would construct and type check +all the ordinary library packages and type-check the packages that +depend on them; then it would add more (test) files to the package and +type-check again. This two-phase approach had four major problems: +1) in processing the tests, the loader modified the library package, + leaving no way for a client application to see both the test + package and the library package; one would mutate into the other. +2) because test files can declare additional methods on types defined in + the library portion of the package, the dispatch of method calls in + the library portion was affected by the presence of the test files. + This should have been a clue that the packages were logically + different. +3) this model of "augmentation" assumed at most one in-package test + per library package, which is true of projects using 'go build', + but not other build systems. +4) because of the two-phase nature of test processing, all packages that + import the library package had to be processed before augmentation, + forcing a "one-shot" API and preventing the client from calling Load + in several times in sequence as is now possible in WholeProgram mode. + (TypeCheck mode has a similar one-shot restriction for a different reason.) + +Early drafts of this package supported "multi-shot" operation +in the Metadata and WholeProgram modes, although this feature is not exposed +through the API and will likely be removed. +Although it allowed clients to make a sequence of calls (or concurrent +calls) to Load, building up the graph of Packages incrementally, +it was of marginal value: it complicated the API +(since it allowed some options to vary across calls but not others), +it complicated the implementation, +it cannot be made to work in TypeCheck mode, as explained above, +and it was less efficient than making one combined call (when this is possible). +Among the clients we have inspected, none made multiple calls to load +but could not be easily and satisfactorily modified to make only a single call. +However, applications changes may be required. +For example, the ssadump command loads the user-specified packages +and in addition the runtime package. It is tempting to simply append +"runtime" to the user-provided list, but that does not work if the user +specified an ad-hoc package such as [a.go b.go]. +Instead, ssadump no longer requests the runtime package, +but seeks it among the dependencies of the user-specified packages, +and emits an error if it is not found. + +Overlays: the ParseFile hook in the API permits clients to vary the way +in which ASTs are obtained from filenames; the default implementation is +based on parser.ParseFile. This features enables editor-integrated tools +that analyze the contents of modified but unsaved buffers: rather than +read from the file system, a tool can read from an archive of modified +buffers provided by the editor. +This approach has its limits. Because package metadata is obtained by +fork/execing an external query command for each build system, we can +fake only the file contents seen by the parser, type-checker, and +application, but not by the metadata query, so, for example: +- additional imports in the fake file will not be described by the + metadata, so the type checker will fail to load imports that create + new dependencies. +- in TypeCheck mode, because export data is produced by the query + command, it will not reflect the fake file contents. +- this mechanism cannot add files to a package without first saving them. + +Questions & Tasks + +- Add GOARCH/GOOS? + They are not portable concepts, but could be made portable. + Our goal has been to allow users to express themselves using the conventions + of the underlying build system: if the build system honors GOARCH + during a build and during a metadata query, then so should + applications built atop that query mechanism. + Conversely, if the target architecture of the build is determined by + command-line flags, the application can pass the relevant + flags through to the build system using a command such as: + myapp -query_flag="--cpu=amd64" -query_flag="--os=darwin" + However, this approach is low-level, unwieldy, and non-portable. + GOOS and GOARCH seem important enough to warrant a dedicated option. + +- How should we handle partial failures such as a mixture of good and + malformed patterns, existing and non-existent packages, successful and + failed builds, import failures, import cycles, and so on, in a call to + Load? + +- Do we need a GeneratedBy map that maps the name of each generated Go + source file in GoFiles to that of the original file, if known, or "" otherwise? + Or are //line directives and "Generated" comments in those files enough? + +- Support bazel, blaze, and go1.10 list, not just go1.11 list. + +- Handle (and test) various partial success cases, e.g. + a mixture of good packages and: + invalid patterns + nonexistent packages + empty packages + packages with malformed package or import declarations + unreadable files + import cycles + other parse errors + type errors + Make sure we record errors at the correct place in the graph. + +- Missing packages among initial arguments are not reported. + Return bogus packages for them, like golist does. + +- "undeclared name" errors (for example) are reported out of source file + order. I suspect this is due to the breadth-first resolution now used + by go/types. Is that a bug? Discuss with gri. + +- https://github.com/golang/go/issues/25980 causes these commands to crash: + $ GOPATH=/none ./gopackages -all all + due to: + $ GOPATH=/none go list -e -test -json all + and: + $ go list -e -test ./relative/path + +- Modify stringer to use go/packages, perhaps initially under flag control. + +- Bug: "gopackages fmt a.go" doesn't produce an error. + +- If necessary, add back an IsTest boolean or expose ForTests on the Package struct. + IsTest was removed because we couldn't agree on a useful definition. + +*/ diff --git a/vendor/golang.org/x/tools/go/packages/external.go b/vendor/golang.org/x/tools/go/packages/external.go new file mode 100644 index 00000000..39e5ed99 --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/external.go @@ -0,0 +1,68 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// This file enables an external tool to intercept package requests. +// If the tool is present then its results are used in preference to +// the go list command. + +package packages + +import ( + "bytes" + "encoding/json" + "fmt" + "os/exec" + "strings" +) + +// findExternalTool returns the file path of a tool that supplies supplies +// the build system package structure, or "" if not found." +// If GOPACKAGESDRIVER is set in the environment findExternalTool returns its +// value, otherwise it searches for a binary named gopackagesdriver on the PATH. +func findExternalDriver(cfg *Config) driver { + const toolPrefix = "GOPACKAGESDRIVER=" + tool := "" + for _, env := range cfg.Env { + if val := strings.TrimPrefix(env, toolPrefix); val != env { + tool = val + } + } + if tool != "" && tool == "off" { + return nil + } + if tool == "" { + var err error + tool, err = exec.LookPath("gopackagesdriver") + if err != nil { + return nil + } + } + return func(cfg *Config, words ...string) (*driverResponse, error) { + buf := new(bytes.Buffer) + fullargs := []string{ + "list", + fmt.Sprintf("-test=%t", cfg.Tests), + fmt.Sprintf("-export=%t", usesExportData(cfg)), + fmt.Sprintf("-deps=%t", cfg.Mode >= LoadImports), + } + for _, f := range cfg.Flags { + fullargs = append(fullargs, fmt.Sprintf("-flags=%v", f)) + } + fullargs = append(fullargs, "--") + fullargs = append(fullargs, words...) + cmd := exec.CommandContext(cfg.Context, tool, fullargs...) + cmd.Env = cfg.Env + cmd.Dir = cfg.Dir + cmd.Stdout = buf + cmd.Stderr = new(bytes.Buffer) + if err := cmd.Run(); err != nil { + return nil, fmt.Errorf("%v: %v: %s", tool, err, cmd.Stderr) + } + var response driverResponse + if err := json.Unmarshal(buf.Bytes(), &response); err != nil { + return nil, err + } + return &response, nil + } +} diff --git a/vendor/golang.org/x/tools/go/packages/golist.go b/vendor/golang.org/x/tools/go/packages/golist.go new file mode 100644 index 00000000..26d62771 --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/golist.go @@ -0,0 +1,337 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package packages + +import ( + "bytes" + "encoding/json" + "fmt" + "log" + "os" + "os/exec" + "path/filepath" + "strings" +) + +// A goTooOldError reports that the go command +// found by exec.LookPath is too old to use the new go list behavior. +type goTooOldError struct { + error +} + +// goListDriver uses the go list command to interpret the patterns and produce +// the build system package structure. +// See driver for more details. +func goListDriver(cfg *Config, patterns ...string) (*driverResponse, error) { + // Determine files requested in contains patterns + var containFiles []string + restPatterns := make([]string, 0, len(patterns)) + for _, pattern := range patterns { + if strings.HasPrefix(pattern, "contains:") { + containFile := strings.TrimPrefix(pattern, "contains:") + containFiles = append(containFiles, containFile) + } else { + restPatterns = append(restPatterns, pattern) + } + } + containFiles = absJoin(cfg.Dir, containFiles) + patterns = restPatterns + + // TODO(matloob): Remove the definition of listfunc and just use golistPackages once go1.12 is released. + var listfunc driver + listfunc = func(cfg *Config, words ...string) (*driverResponse, error) { + response, err := golistDriverCurrent(cfg, patterns...) + if _, ok := err.(goTooOldError); ok { + listfunc = golistDriverFallback + return listfunc(cfg, patterns...) + } + listfunc = golistDriverCurrent + return response, err + } + + var response *driverResponse + var err error + + // see if we have any patterns to pass through to go list. + if len(patterns) > 0 { + response, err = listfunc(cfg, patterns...) + if err != nil { + return nil, err + } + } else { + response = &driverResponse{} + } + + // Run go list for contains: patterns. + seenPkgs := make(map[string]*Package) // for deduplication. different containing queries could produce same packages + if len(containFiles) > 0 { + for _, pkg := range response.Packages { + seenPkgs[pkg.ID] = pkg + } + } + for _, f := range containFiles { + // TODO(matloob): Do only one query per directory. + fdir := filepath.Dir(f) + cfg.Dir = fdir + dirResponse, err := listfunc(cfg, ".") + if err != nil { + return nil, err + } + isRoot := make(map[string]bool, len(dirResponse.Roots)) + for _, root := range dirResponse.Roots { + isRoot[root] = true + } + for _, pkg := range dirResponse.Packages { + // Add any new packages to the main set + // We don't bother to filter packages that will be dropped by the changes of roots, + // that will happen anyway during graph construction outside this function. + // Over-reporting packages is not a problem. + if _, ok := seenPkgs[pkg.ID]; !ok { + // it is a new package, just add it + seenPkgs[pkg.ID] = pkg + response.Packages = append(response.Packages, pkg) + } + // if the package was not a root one, it cannot have the file + if !isRoot[pkg.ID] { + continue + } + for _, pkgFile := range pkg.GoFiles { + if filepath.Base(f) == filepath.Base(pkgFile) { + response.Roots = append(response.Roots, pkg.ID) + break + } + } + } + } + return response, nil +} + +// Fields must match go list; +// see $GOROOT/src/cmd/go/internal/load/pkg.go. +type jsonPackage struct { + ImportPath string + Dir string + Name string + Export string + GoFiles []string + CompiledGoFiles []string + CFiles []string + CgoFiles []string + CXXFiles []string + MFiles []string + HFiles []string + FFiles []string + SFiles []string + SwigFiles []string + SwigCXXFiles []string + SysoFiles []string + Imports []string + ImportMap map[string]string + Deps []string + TestGoFiles []string + TestImports []string + XTestGoFiles []string + XTestImports []string + ForTest string // q in a "p [q.test]" package, else "" + DepOnly bool +} + +func otherFiles(p *jsonPackage) [][]string { + return [][]string{p.CFiles, p.CXXFiles, p.MFiles, p.HFiles, p.FFiles, p.SFiles, p.SwigFiles, p.SwigCXXFiles, p.SysoFiles} +} + +// golistDriverCurrent uses the "go list" command to expand the +// pattern words and return metadata for the specified packages. +// dir may be "" and env may be nil, as per os/exec.Command. +func golistDriverCurrent(cfg *Config, words ...string) (*driverResponse, error) { + // go list uses the following identifiers in ImportPath and Imports: + // + // "p" -- importable package or main (command) + // "q.test" -- q's test executable + // "p [q.test]" -- variant of p as built for q's test executable + // "q_test [q.test]" -- q's external test package + // + // The packages p that are built differently for a test q.test + // are q itself, plus any helpers used by the external test q_test, + // typically including "testing" and all its dependencies. + + // Run "go list" for complete + // information on the specified packages. + buf, err := golist(cfg, golistargs(cfg, words)) + if err != nil { + return nil, err + } + // Decode the JSON and convert it to Package form. + var response driverResponse + for dec := json.NewDecoder(buf); dec.More(); { + p := new(jsonPackage) + if err := dec.Decode(p); err != nil { + return nil, fmt.Errorf("JSON decoding failed: %v", err) + } + + // Bad package? + if p.Name == "" { + // This could be due to: + // - no such package + // - package directory contains no Go source files + // - all package declarations are mangled + // - and possibly other things. + // + // For now, we throw it away and let later + // stages rediscover the problem, but this + // discards the error message computed by go list + // and computes a new one---by different logic: + // if only one of the package declarations is + // bad, for example, should we report an error + // in Metadata mode? + // Unless we parse and typecheck, we might not + // notice there's a problem. + // + // Perhaps we should save a map of PackageID to + // errors for such cases. + continue + } + + id := p.ImportPath + + // Extract the PkgPath from the package's ID. + pkgpath := id + if i := strings.IndexByte(id, ' '); i >= 0 { + pkgpath = id[:i] + } + + if pkgpath == "unsafe" { + p.GoFiles = nil // ignore fake unsafe.go file + } + + // Assume go list emits only absolute paths for Dir. + if !filepath.IsAbs(p.Dir) { + log.Fatalf("internal error: go list returned non-absolute Package.Dir: %s", p.Dir) + } + + export := p.Export + if export != "" && !filepath.IsAbs(export) { + export = filepath.Join(p.Dir, export) + } + + // imports + // + // Imports contains the IDs of all imported packages. + // ImportsMap records (path, ID) only where they differ. + ids := make(map[string]bool) + for _, id := range p.Imports { + ids[id] = true + } + imports := make(map[string]*Package) + for path, id := range p.ImportMap { + imports[path] = &Package{ID: id} // non-identity import + delete(ids, id) + } + for id := range ids { + if id == "C" { + continue + } + + imports[id] = &Package{ID: id} // identity import + } + if !p.DepOnly { + response.Roots = append(response.Roots, id) + } + pkg := &Package{ + ID: id, + Name: p.Name, + PkgPath: pkgpath, + GoFiles: absJoin(p.Dir, p.GoFiles, p.CgoFiles), + CompiledGoFiles: absJoin(p.Dir, p.CompiledGoFiles), + OtherFiles: absJoin(p.Dir, otherFiles(p)...), + Imports: imports, + ExportFile: export, + } + // TODO(matloob): Temporary hack since CompiledGoFiles isn't always set. + if len(pkg.CompiledGoFiles) == 0 { + pkg.CompiledGoFiles = pkg.GoFiles + } + response.Packages = append(response.Packages, pkg) + } + + return &response, nil +} + +// absJoin absolutizes and flattens the lists of files. +func absJoin(dir string, fileses ...[]string) (res []string) { + for _, files := range fileses { + for _, file := range files { + if !filepath.IsAbs(file) { + file = filepath.Join(dir, file) + } + res = append(res, file) + } + } + return res +} + +func golistargs(cfg *Config, words []string) []string { + fullargs := []string{ + "list", "-e", "-json", "-compiled", + fmt.Sprintf("-test=%t", cfg.Tests), + fmt.Sprintf("-export=%t", usesExportData(cfg)), + fmt.Sprintf("-deps=%t", cfg.Mode >= LoadImports), + } + fullargs = append(fullargs, cfg.Flags...) + fullargs = append(fullargs, "--") + fullargs = append(fullargs, words...) + return fullargs +} + +// golist returns the JSON-encoded result of a "go list args..." query. +func golist(cfg *Config, args []string) (*bytes.Buffer, error) { + out := new(bytes.Buffer) + cmd := exec.CommandContext(cfg.Context, "go", args...) + cmd.Env = cfg.Env + cmd.Dir = cfg.Dir + cmd.Stdout = out + cmd.Stderr = new(bytes.Buffer) + if err := cmd.Run(); err != nil { + exitErr, ok := err.(*exec.ExitError) + if !ok { + // Catastrophic error: + // - executable not found + // - context cancellation + return nil, fmt.Errorf("couldn't exec 'go list': %s %T", err, err) + } + + // Old go list? + if strings.Contains(fmt.Sprint(cmd.Stderr), "flag provided but not defined") { + return nil, goTooOldError{fmt.Errorf("unsupported version of go list: %s: %s", exitErr, cmd.Stderr)} + } + + // Export mode entails a build. + // If that build fails, errors appear on stderr + // (despite the -e flag) and the Export field is blank. + // Do not fail in that case. + if !usesExportData(cfg) { + return nil, fmt.Errorf("go list: %s: %s", exitErr, cmd.Stderr) + } + } + + // Print standard error output from "go list". + // Due to the -e flag, this should be empty. + // However, in -export mode it contains build errors. + // Should go list save build errors in the Package.Error JSON field? + // See https://github.com/golang/go/issues/26319. + // If so, then we should continue to print stderr as go list + // will be silent unless something unexpected happened. + // If not, perhaps we should suppress it to reduce noise. + if stderr := fmt.Sprint(cmd.Stderr); stderr != "" { + fmt.Fprintf(os.Stderr, "go list stderr <<%s>>\n", stderr) + } + + // debugging + if false { + fmt.Fprintln(os.Stderr, out) + } + + return out, nil +} diff --git a/vendor/golang.org/x/tools/go/packages/golist_fallback.go b/vendor/golang.org/x/tools/go/packages/golist_fallback.go new file mode 100644 index 00000000..331bb655 --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/golist_fallback.go @@ -0,0 +1,282 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package packages + +import ( + "encoding/json" + "fmt" + + "go/build" + "io/ioutil" + "os" + "path/filepath" + "sort" + "strings" + + "golang.org/x/tools/go/internal/cgo" +) + +// TODO(matloob): Delete this file once Go 1.12 is released. + +// This file provides backwards compatibility support for +// loading for versions of Go earlier than 1.10.4. This support is meant to +// assist with migration to the Package API until there's +// widespread adoption of these newer Go versions. +// This support will be removed once Go 1.12 is released +// in Q1 2019. + +func golistDriverFallback(cfg *Config, words ...string) (*driverResponse, error) { + original, deps, err := getDeps(cfg, words...) + if err != nil { + return nil, err + } + + var tmpdir string // used for generated cgo files + + var response driverResponse + addPackage := func(p *jsonPackage) { + if p.Name == "" { + return + } + + id := p.ImportPath + isRoot := original[id] != nil + pkgpath := id + + if pkgpath == "unsafe" { + p.GoFiles = nil // ignore fake unsafe.go file + } + + importMap := func(importlist []string) map[string]*Package { + importMap := make(map[string]*Package) + for _, id := range importlist { + + if id == "C" { + for _, path := range []string{"unsafe", "syscall", "runtime/cgo"} { + if pkgpath != path && importMap[path] == nil { + importMap[path] = &Package{ID: path} + } + } + continue + } + importMap[vendorlessPath(id)] = &Package{ID: id} + } + return importMap + } + compiledGoFiles := absJoin(p.Dir, p.GoFiles) + // Use a function to simplify control flow. It's just a bunch of gotos. + var cgoErrors []error + processCgo := func() bool { + // Suppress any cgo errors. Any relevant errors will show up in typechecking. + // TODO(matloob): Skip running cgo if Mode < LoadTypes. + if tmpdir == "" { + if tmpdir, err = ioutil.TempDir("", "gopackages"); err != nil { + cgoErrors = append(cgoErrors, err) + return false + } + } + outdir := filepath.Join(tmpdir, strings.Replace(p.ImportPath, "/", "_", -1)) + if err := os.Mkdir(outdir, 0755); err != nil { + cgoErrors = append(cgoErrors, err) + return false + } + files, _, err := runCgo(p.Dir, outdir, cfg.Env) + if err != nil { + cgoErrors = append(cgoErrors, err) + return false + } + compiledGoFiles = append(compiledGoFiles, files...) + return true + } + if len(p.CgoFiles) == 0 || !processCgo() { + compiledGoFiles = append(compiledGoFiles, absJoin(p.Dir, p.CgoFiles)...) // Punt to typechecker. + } + if isRoot { + response.Roots = append(response.Roots, id) + } + response.Packages = append(response.Packages, &Package{ + ID: id, + Name: p.Name, + GoFiles: absJoin(p.Dir, p.GoFiles, p.CgoFiles), + CompiledGoFiles: compiledGoFiles, + OtherFiles: absJoin(p.Dir, otherFiles(p)...), + PkgPath: pkgpath, + Imports: importMap(p.Imports), + // TODO(matloob): set errors on the Package to cgoErrors + }) + if cfg.Tests { + testID := fmt.Sprintf("%s [%s.test]", id, id) + if len(p.TestGoFiles) > 0 || len(p.XTestGoFiles) > 0 { + if isRoot { + response.Roots = append(response.Roots, testID) + } + response.Packages = append(response.Packages, &Package{ + ID: testID, + Name: p.Name, + GoFiles: absJoin(p.Dir, p.GoFiles, p.CgoFiles, p.TestGoFiles), + CompiledGoFiles: append(compiledGoFiles, absJoin(p.Dir, p.TestGoFiles)...), + OtherFiles: absJoin(p.Dir, otherFiles(p)...), + PkgPath: pkgpath, + Imports: importMap(append(p.Imports, p.TestImports...)), + // TODO(matloob): set errors on the Package to cgoErrors + }) + if len(p.XTestGoFiles) > 0 { + xtestID := fmt.Sprintf("%s_test [%s.test]", id, id) + if isRoot { + response.Roots = append(response.Roots, xtestID) + } + for i, imp := range p.XTestImports { + if imp == p.ImportPath { + p.XTestImports[i] = testID + break + } + } + response.Packages = append(response.Packages, &Package{ + ID: xtestID, + Name: p.Name + "_test", + GoFiles: absJoin(p.Dir, p.XTestGoFiles), + CompiledGoFiles: absJoin(p.Dir, p.XTestGoFiles), + PkgPath: pkgpath, + Imports: importMap(p.XTestImports), + }) + } + } + } + } + + for _, pkg := range original { + addPackage(pkg) + } + if cfg.Mode < LoadImports || len(deps) == 0 { + return &response, nil + } + + buf, err := golist(cfg, golistArgsFallback(cfg, deps)) + if err != nil { + return nil, err + } + + // Decode the JSON and convert it to Package form. + for dec := json.NewDecoder(buf); dec.More(); { + p := new(jsonPackage) + if err := dec.Decode(p); err != nil { + return nil, fmt.Errorf("JSON decoding failed: %v", err) + } + + addPackage(p) + } + + return &response, nil +} + +// vendorlessPath returns the devendorized version of the import path ipath. +// For example, VendorlessPath("foo/bar/vendor/a/b") returns "a/b". +// Copied from golang.org/x/tools/imports/fix.go. +func vendorlessPath(ipath string) string { + // Devendorize for use in import statement. + if i := strings.LastIndex(ipath, "/vendor/"); i >= 0 { + return ipath[i+len("/vendor/"):] + } + if strings.HasPrefix(ipath, "vendor/") { + return ipath[len("vendor/"):] + } + return ipath +} + +// getDeps runs an initial go list to determine all the dependency packages. +func getDeps(cfg *Config, words ...string) (originalSet map[string]*jsonPackage, deps []string, err error) { + buf, err := golist(cfg, golistArgsFallback(cfg, words)) + if err != nil { + return nil, nil, err + } + + depsSet := make(map[string]bool) + originalSet = make(map[string]*jsonPackage) + var testImports []string + + // Extract deps from the JSON. + for dec := json.NewDecoder(buf); dec.More(); { + p := new(jsonPackage) + if err := dec.Decode(p); err != nil { + return nil, nil, fmt.Errorf("JSON decoding failed: %v", err) + } + + originalSet[p.ImportPath] = p + for _, dep := range p.Deps { + depsSet[dep] = true + } + if cfg.Tests { + // collect the additional imports of the test packages. + pkgTestImports := append(p.TestImports, p.XTestImports...) + for _, imp := range pkgTestImports { + if depsSet[imp] { + continue + } + depsSet[imp] = true + testImports = append(testImports, imp) + } + } + } + // Get the deps of the packages imported by tests. + if len(testImports) > 0 { + buf, err = golist(cfg, golistArgsFallback(cfg, testImports)) + if err != nil { + return nil, nil, err + } + // Extract deps from the JSON. + for dec := json.NewDecoder(buf); dec.More(); { + p := new(jsonPackage) + if err := dec.Decode(p); err != nil { + return nil, nil, fmt.Errorf("JSON decoding failed: %v", err) + } + for _, dep := range p.Deps { + depsSet[dep] = true + } + } + } + + for orig := range originalSet { + delete(depsSet, orig) + } + + deps = make([]string, 0, len(depsSet)) + for dep := range depsSet { + deps = append(deps, dep) + } + sort.Strings(deps) // ensure output is deterministic + return originalSet, deps, nil +} + +func golistArgsFallback(cfg *Config, words []string) []string { + fullargs := []string{"list", "-e", "-json"} + fullargs = append(fullargs, cfg.Flags...) + fullargs = append(fullargs, "--") + fullargs = append(fullargs, words...) + return fullargs +} + +func runCgo(pkgdir, tmpdir string, env []string) (files, displayfiles []string, err error) { + // Use go/build to open cgo files and determine the cgo flags, etc, from them. + // This is tricky so it's best to avoid reimplementing as much as we can, and + // we plan to delete this support once Go 1.12 is released anyways. + // TODO(matloob): This isn't completely correct because we're using the Default + // context. Perhaps we should more accurately fill in the context. + bp, err := build.ImportDir(pkgdir, build.ImportMode(0)) + if err != nil { + return nil, nil, err + } + for _, ev := range env { + if v := strings.TrimPrefix(ev, "CGO_CPPFLAGS"); v != ev { + bp.CgoCPPFLAGS = append(bp.CgoCPPFLAGS, strings.Fields(v)...) + } else if v := strings.TrimPrefix(ev, "CGO_CFLAGS"); v != ev { + bp.CgoCFLAGS = append(bp.CgoCFLAGS, strings.Fields(v)...) + } else if v := strings.TrimPrefix(ev, "CGO_CXXFLAGS"); v != ev { + bp.CgoCXXFLAGS = append(bp.CgoCXXFLAGS, strings.Fields(v)...) + } else if v := strings.TrimPrefix(ev, "CGO_LDFLAGS"); v != ev { + bp.CgoLDFLAGS = append(bp.CgoLDFLAGS, strings.Fields(v)...) + } + } + return cgo.Run(bp, pkgdir, tmpdir, true) +} diff --git a/vendor/golang.org/x/tools/go/packages/packages.go b/vendor/golang.org/x/tools/go/packages/packages.go new file mode 100644 index 00000000..7e8e4e2e --- /dev/null +++ b/vendor/golang.org/x/tools/go/packages/packages.go @@ -0,0 +1,824 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package packages + +// See doc.go for package documentation and implementation notes. + +import ( + "context" + "encoding/json" + "fmt" + "go/ast" + "go/parser" + "go/token" + "go/types" + "log" + "os" + "sync" + + "golang.org/x/tools/go/gcexportdata" +) + +// A LoadMode specifies the amount of detail to return when loading packages. +// The modes are all strictly additive, as you go through the list it increases +// the amount of information available to you, but may also increase the cost +// of collecting the information. +// Load is always allowed to return more information than requested. +type LoadMode int + +const ( + // LoadFiles finds the packages and computes their source file lists. + // Package fields: ID, Name, Errors, GoFiles, OtherFiles. + LoadFiles LoadMode = iota + + // LoadImports adds import information for each package + // and its dependencies. + // Package fields added: Imports. + LoadImports + + // LoadTypes adds type information for the package's exported symbols. + // Package fields added: Types, Fset, IllTyped. + // This will use the type information provided by the build system if + // possible, and the ExportFile field may be filled in. + LoadTypes + + // LoadSyntax adds typed syntax trees for the packages matching the patterns. + // Package fields added: Syntax, TypesInfo, for direct pattern matches only. + LoadSyntax + + // LoadAllSyntax adds typed syntax trees for the packages matching the patterns + // and all dependencies. + // Package fields added: Syntax, TypesInfo, for all packages in import graph. + LoadAllSyntax +) + +// An Config specifies details about how packages should be loaded. +// Calls to Load do not modify this struct. +type Config struct { + // Mode controls the level of information returned for each package. + Mode LoadMode + + // Context specifies the context for the load operation. + // If the context is cancelled, the loader may stop early + // and return an ErrCancelled error. + // If Context is nil, the load cannot be cancelled. + Context context.Context + + // Dir is the directory in which to run the build system tool + // that provides information about the packages. + // If Dir is empty, the tool is run in the current directory. + Dir string + + // Env is the environment to use when invoking the build system tool. + // If Env is nil, the current environment is used. + // Like in os/exec's Cmd, only the last value in the slice for + // each environment key is used. To specify the setting of only + // a few variables, append to the current environment, as in: + // + // opt.Env = append(os.Environ(), "GOOS=plan9", "GOARCH=386") + // + Env []string + + // Flags is a list of command-line flags to be passed through to + // the underlying query tool. + Flags []string + + // Error is called for each error encountered during package loading. + // It must be safe to call Error simultaneously from multiple goroutines. + // In addition to calling Error, the loader will record each error + // in the corresponding Package's Errors list. + // If Error is nil, the loader will print errors to os.Stderr. + // To disable printing of errors, set opt.Error = func(error){}. + // TODO(rsc): What happens in the Metadata loader? Currently nothing. + Error func(error) + + // Fset is the token.FileSet to use when parsing source files or + // type information provided by the build system. + // If Fset is nil, the loader will create one. + Fset *token.FileSet + + // ParseFile is called to read and parse each file + // when preparing a package's type-checked syntax tree. + // It must be safe to call ParseFile simultaneously from multiple goroutines. + // If ParseFile is nil, the loader will uses parser.ParseFile. + // + // Setting ParseFile to a custom implementation can allow + // providing alternate file content in order to type-check + // unsaved text editor buffers, or to selectively eliminate + // unwanted function bodies to reduce the amount of work + // done by the type checker. + ParseFile func(fset *token.FileSet, filename string) (*ast.File, error) + + // If Tests is set, the loader includes not just the packages + // matching a particular pattern but also any related test packages, + // including test-only variants of the package and the test executable. + // + // For example, when using the go command, loading "fmt" with Tests=true + // returns four packages, with IDs "fmt" (the standard package), + // "fmt [fmt.test]" (the package as compiled for the test), + // "fmt_test" (the test functions from source files in package fmt_test), + // and "fmt.test" (the test binary). + // + // In build systems with explicit names for tests, + // setting Tests may have no effect. + Tests bool + + // TypeChecker provides additional configuration for type-checking syntax trees. + // + // It is used for all packages in LoadAllSyntax mode, + // and for the packages matching the patterns, but not their dependencies, + // in LoadSyntax mode. + // + // The TypeChecker.Error function is ignored: + // errors are reported using the Error function defined above. + // + // The TypeChecker.Importer function is ignored: + // the loader defines an appropriate importer. + // + // TODO(rsc): TypeChecker.Sizes should use the same sizes as the main build. + // Derive them from the runtime? + TypeChecker types.Config +} + +// driver is the type for functions that query the build system for the +// packages named by the patterns. +type driver func(cfg *Config, patterns ...string) (*driverResponse, error) + +// driverResponse contains the results for a driver query. +type driverResponse struct { + // Roots is the set of package IDs that make up the root packages. + // We have to encode this separately because when we encode a single package + // we cannot know if it is one of the roots as that requires knowledge of the + // graph it is part of. + Roots []string `json:",omitempty"` + + // Packages is the full set of packages in the graph. + // The packages are not connected into a graph. + // The Imports if populated will be stubs that only have their ID set. + // Imports will be connected and then type and syntax information added in a + // later pass (see refine). + Packages []*Package +} + +// Load loads and returns the Go packages named by the given patterns. +// +// Config specifies loading options; +// nil behaves the same as an empty Config. +// +// Load returns an error if any of the patterns was invalid +// as defined by the underlying build system. +// It may return an empty list of packages without an error, +// for instance for an empty expansion of a valid wildcard. +func Load(cfg *Config, patterns ...string) ([]*Package, error) { + l := newLoader(cfg) + response, err := defaultDriver(&l.Config, patterns...) + if err != nil { + return nil, err + } + return l.refine(response.Roots, response.Packages...) +} + +// defaultDriver is a driver that looks for an external driver binary, and if +// it does not find it falls back to the built in go list driver. +func defaultDriver(cfg *Config, patterns ...string) (*driverResponse, error) { + driver := findExternalDriver(cfg) + if driver == nil { + driver = goListDriver + } + return driver(cfg, patterns...) +} + +// A Package describes a single loaded Go package. +type Package struct { + // ID is a unique identifier for a package, + // in a syntax provided by the underlying build system. + // + // Because the syntax varies based on the build system, + // clients should treat IDs as opaque and not attempt to + // interpret them. + ID string + + // Name is the package name as it appears in the package source code. + Name string + + // This is the package path as used by the types package. + // This is used to map entries in the type information back to the package + // they come from. + PkgPath string + + // Errors lists any errors encountered while loading the package. + // TODO(rsc): Say something about the errors or at least their Strings, + // as far as file:line being at the beginning and so on. + Errors []error + + // GoFiles lists the absolute file paths of the package's Go source files. + GoFiles []string + + // CompiledGoFiles lists the absolute file paths of the package's source + // files that were presented to the compiler. + // This may differ from GoFiles if files are processed before compilation. + CompiledGoFiles []string + + // OtherFiles lists the absolute file paths of the package's non-Go source files, + // including assembly, C, C++, Fortran, Objective-C, SWIG, and so on. + OtherFiles []string + + // ExportFile is the absolute path to a file containing the type information + // provided by the build system. + ExportFile string + + // Imports maps import paths appearing in the package's Go source files + // to corresponding loaded Packages. + Imports map[string]*Package + + // Types is the type information for the package. + // Modes LoadTypes and above set this field for all packages. + // + // TODO(adonovan): all packages? In Types mode this entails + // asymptotically more export data processing than is required + // to load the requested packages. Is that what we want? + Types *types.Package + + // Fset provides position information for Types, TypesInfo, and Syntax. + // Modes LoadTypes and above set this field for all packages. + Fset *token.FileSet + + // IllTyped indicates whether the package has any type errors. + // Modes LoadTypes and above set this field for all packages. + IllTyped bool + + // Syntax is the package's syntax trees, for the files listed in GoFiles. + // + // Mode LoadSyntax set this field for packages matching the patterns. + // Mode LoadSyntaxAll sets this field for all packages, including dependencies. + Syntax []*ast.File + + // TypesInfo is the type-checking results for the package's syntax trees. + // It is set only when Syntax is set. + TypesInfo *types.Info +} + +// packageError is used to serialize structured errors as much as possible. +// This has members compatible with the golist error type, and possibly some +// more if we need other error information to survive. +type packageError struct { + Pos string // position of error + Err string // the error itself +} + +func (e *packageError) Error() string { + return e.Pos + ": " + e.Err +} + +// flatPackage is the JSON form of Package +// It drops all the type and syntax fields, and transforms the Imports and Errors +type flatPackage struct { + ID string + Name string `json:",omitempty"` + PkgPath string `json:",omitempty"` + Errors []*packageError `json:",omitempty"` + GoFiles []string `json:",omitempty"` + CompiledGoFiles []string `json:",omitempty"` + OtherFiles []string `json:",omitempty"` + ExportFile string `json:",omitempty"` + Imports map[string]string `json:",omitempty"` +} + +// MarshalJSON returns the Package in its JSON form. +// For the most part, the structure fields are written out unmodified, and +// the type and syntax fields are skipped. +// The imports are written out as just a map of path to package id. +// The errors are written using a custom type that tries to preserve the +// structure of error types we know about. +// This method exists to enable support for additional build systems. It is +// not intended for use by clients of the API and we may change the format. +func (p *Package) MarshalJSON() ([]byte, error) { + flat := &flatPackage{ + ID: p.ID, + Name: p.Name, + PkgPath: p.PkgPath, + GoFiles: p.GoFiles, + CompiledGoFiles: p.CompiledGoFiles, + OtherFiles: p.OtherFiles, + ExportFile: p.ExportFile, + } + if len(p.Errors) > 0 { + flat.Errors = make([]*packageError, len(p.Errors)) + for i, err := range p.Errors { + //TODO: best effort mapping of errors to the serialized form + switch err := err.(type) { + case *packageError: + flat.Errors[i] = err + default: + flat.Errors[i] = &packageError{Err: err.Error()} + } + } + } + if len(p.Imports) > 0 { + flat.Imports = make(map[string]string, len(p.Imports)) + for path, ipkg := range p.Imports { + flat.Imports[path] = ipkg.ID + } + } + return json.Marshal(flat) +} + +// UnmarshalJSON reads in a Package from its JSON format. +// See MarshalJSON for details about the format accepted. +func (p *Package) UnmarshalJSON(b []byte) error { + flat := &flatPackage{} + if err := json.Unmarshal(b, &flat); err != nil { + return err + } + *p = Package{ + ID: flat.ID, + Name: flat.Name, + PkgPath: flat.PkgPath, + GoFiles: flat.GoFiles, + CompiledGoFiles: flat.CompiledGoFiles, + OtherFiles: flat.OtherFiles, + ExportFile: flat.ExportFile, + } + if len(flat.Errors) > 0 { + p.Errors = make([]error, len(flat.Errors)) + for i, err := range flat.Errors { + p.Errors[i] = err + } + } + if len(flat.Imports) > 0 { + p.Imports = make(map[string]*Package, len(flat.Imports)) + for path, id := range flat.Imports { + p.Imports[path] = &Package{ID: id} + } + } + return nil +} + +func (p *Package) String() string { return p.ID } + +// loaderPackage augments Package with state used during the loading phase +type loaderPackage struct { + *Package + importErrors map[string]error // maps each bad import to its error + loadOnce sync.Once + color uint8 // for cycle detection + mark, needsrc bool // used when Mode >= LoadTypes +} + +// loader holds the working state of a single call to load. +type loader struct { + pkgs map[string]*loaderPackage + Config + exportMu sync.Mutex // enforces mutual exclusion of exportdata operations +} + +func newLoader(cfg *Config) *loader { + ld := &loader{} + if cfg != nil { + ld.Config = *cfg + } + if ld.Context == nil { + ld.Context = context.Background() + } + if ld.Dir == "" { + if dir, err := os.Getwd(); err == nil { + ld.Dir = dir + } + } + + if ld.Mode >= LoadTypes { + if ld.Fset == nil { + ld.Fset = token.NewFileSet() + } + + // Error and ParseFile are required even in LoadTypes mode + // because we load source if export data is missing. + + if ld.Error == nil { + ld.Error = func(e error) { + fmt.Fprintln(os.Stderr, e) + } + } + + if ld.ParseFile == nil { + ld.ParseFile = func(fset *token.FileSet, filename string) (*ast.File, error) { + const mode = parser.AllErrors | parser.ParseComments + return parser.ParseFile(fset, filename, nil, mode) + } + } + } + return ld +} + +// refine connects the supplied packages into a graph and then adds type and +// and syntax information as requested by the LoadMode. +func (ld *loader) refine(roots []string, list ...*Package) ([]*Package, error) { + if len(list) == 0 { + return nil, fmt.Errorf("packages not found") + } + isRoot := make(map[string]bool, len(roots)) + for _, root := range roots { + isRoot[root] = true + } + ld.pkgs = make(map[string]*loaderPackage) + // first pass, fixup and build the map and roots + var initial []*loaderPackage + for _, pkg := range list { + lpkg := &loaderPackage{ + Package: pkg, + needsrc: ld.Mode >= LoadAllSyntax || + (ld.Mode >= LoadSyntax && isRoot[pkg.ID]) || + (pkg.ExportFile == "" && pkg.PkgPath != "unsafe"), + } + ld.pkgs[lpkg.ID] = lpkg + if isRoot[lpkg.ID] { + initial = append(initial, lpkg) + } + } + + // Materialize the import graph. + + const ( + white = 0 // new + grey = 1 // in progress + black = 2 // complete + ) + + // visit traverses the import graph, depth-first, + // and materializes the graph as Packages.Imports. + // + // Valid imports are saved in the Packages.Import map. + // Invalid imports (cycles and missing nodes) are saved in the importErrors map. + // Thus, even in the presence of both kinds of errors, the Import graph remains a DAG. + // + // visit returns whether the package needs src or has a transitive + // dependency on a package that does. These are the only packages + // for which we load source code. + var stack []*loaderPackage + var visit func(lpkg *loaderPackage) bool + visit = func(lpkg *loaderPackage) bool { + switch lpkg.color { + case black: + return lpkg.needsrc + case grey: + panic("internal error: grey node") + } + lpkg.color = grey + stack = append(stack, lpkg) // push + stubs := lpkg.Imports // the structure form has only stubs with the ID in the Imports + lpkg.Imports = make(map[string]*Package, len(stubs)) + for importPath, ipkg := range stubs { + var importErr error + imp := ld.pkgs[ipkg.ID] + if imp == nil { + // (includes package "C" when DisableCgo) + importErr = fmt.Errorf("missing package: %q", ipkg.ID) + } else if imp.color == grey { + importErr = fmt.Errorf("import cycle: %s", stack) + } + if importErr != nil { + if lpkg.importErrors == nil { + lpkg.importErrors = make(map[string]error) + } + lpkg.importErrors[importPath] = importErr + continue + } + + if visit(imp) { + lpkg.needsrc = true + } + lpkg.Imports[importPath] = imp.Package + } + + stack = stack[:len(stack)-1] // pop + lpkg.color = black + + return lpkg.needsrc + } + + if ld.Mode < LoadImports { + //we do this to drop the stub import packages that we are not even going to try to resolve + for _, lpkg := range initial { + lpkg.Imports = nil + } + } else { + // For each initial package, create its import DAG. + for _, lpkg := range initial { + visit(lpkg) + } + } + // Load type data if needed, starting at + // the initial packages (roots of the import DAG). + if ld.Mode >= LoadTypes { + var wg sync.WaitGroup + for _, lpkg := range initial { + wg.Add(1) + go func(lpkg *loaderPackage) { + ld.loadRecursive(lpkg) + wg.Done() + }(lpkg) + } + wg.Wait() + } + + result := make([]*Package, len(initial)) + for i, lpkg := range initial { + result[i] = lpkg.Package + } + return result, nil +} + +// loadRecursive loads the specified package and its dependencies, +// recursively, in parallel, in topological order. +// It is atomic and idempotent. +// Precondition: ld.Mode >= LoadTypes. +func (ld *loader) loadRecursive(lpkg *loaderPackage) { + lpkg.loadOnce.Do(func() { + // Load the direct dependencies, in parallel. + var wg sync.WaitGroup + for _, ipkg := range lpkg.Imports { + imp := ld.pkgs[ipkg.ID] + wg.Add(1) + go func(imp *loaderPackage) { + ld.loadRecursive(imp) + wg.Done() + }(imp) + } + wg.Wait() + + ld.loadPackage(lpkg) + }) +} + +// loadPackage loads the specified package. +// It must be called only once per Package, +// after immediate dependencies are loaded. +// Precondition: ld.Mode >= LoadTypes. +func (ld *loader) loadPackage(lpkg *loaderPackage) { + if lpkg.PkgPath == "unsafe" { + // Fill in the blanks to avoid surprises. + lpkg.Types = types.Unsafe + lpkg.Fset = ld.Fset + lpkg.Syntax = []*ast.File{} + lpkg.TypesInfo = new(types.Info) + return + } + + // Call NewPackage directly with explicit name. + // This avoids skew between golist and go/types when the files' + // package declarations are inconsistent. + lpkg.Types = types.NewPackage(lpkg.PkgPath, lpkg.Name) + + if !lpkg.needsrc { + ld.loadFromExportData(lpkg) + return // not a source package, don't get syntax trees + } + + hardErrors := false + appendError := func(err error) { + if terr, ok := err.(types.Error); ok && terr.Soft { + // Don't mark the package as bad. + } else { + hardErrors = true + } + ld.Error(err) + lpkg.Errors = append(lpkg.Errors, err) + } + + files, errs := ld.parseFiles(lpkg.CompiledGoFiles) + for _, err := range errs { + appendError(err) + } + + lpkg.Fset = ld.Fset + lpkg.Syntax = files + + lpkg.TypesInfo = &types.Info{ + Types: make(map[ast.Expr]types.TypeAndValue), + Defs: make(map[*ast.Ident]types.Object), + Uses: make(map[*ast.Ident]types.Object), + Implicits: make(map[ast.Node]types.Object), + Scopes: make(map[ast.Node]*types.Scope), + Selections: make(map[*ast.SelectorExpr]*types.Selection), + } + + // Copy the prototype types.Config as it must vary across Packages. + tc := ld.TypeChecker // copy + tc.Importer = importerFunc(func(path string) (*types.Package, error) { + if path == "unsafe" { + return types.Unsafe, nil + } + + // The imports map is keyed by import path. + ipkg := lpkg.Imports[path] + if ipkg == nil { + if err := lpkg.importErrors[path]; err != nil { + return nil, err + } + // There was skew between the metadata and the + // import declarations, likely due to an edit + // race, or because the ParseFile feature was + // used to supply alternative file contents. + return nil, fmt.Errorf("no metadata for %s", path) + } + + if ipkg.Types != nil && ipkg.Types.Complete() { + return ipkg.Types, nil + } + log.Fatalf("internal error: nil Pkg importing %q from %q", path, lpkg) + panic("unreachable") + }) + tc.Error = appendError + + // type-check + types.NewChecker(&tc, ld.Fset, lpkg.Types, lpkg.TypesInfo).Files(lpkg.Syntax) + + lpkg.importErrors = nil // no longer needed + + // If !Cgo, the type-checker uses FakeImportC mode, so + // it doesn't invoke the importer for import "C", + // nor report an error for the import, + // or for any undefined C.f reference. + // We must detect this explicitly and correctly + // mark the package as IllTyped (by reporting an error). + // TODO(adonovan): if these errors are annoying, + // we could just set IllTyped quietly. + if tc.FakeImportC { + outer: + for _, f := range lpkg.Syntax { + for _, imp := range f.Imports { + if imp.Path.Value == `"C"` { + appendError(fmt.Errorf(`%s: import "C" ignored`, + lpkg.Fset.Position(imp.Pos()))) + break outer + } + } + } + } + + // Record accumulated errors. + for _, imp := range lpkg.Imports { + if imp.IllTyped { + hardErrors = true + break + } + } + + lpkg.IllTyped = hardErrors +} + +// An importFunc is an implementation of the single-method +// types.Importer interface based on a function value. +type importerFunc func(path string) (*types.Package, error) + +func (f importerFunc) Import(path string) (*types.Package, error) { return f(path) } + +// We use a counting semaphore to limit +// the number of parallel I/O calls per process. +var ioLimit = make(chan bool, 20) + +// parseFiles reads and parses the Go source files and returns the ASTs +// of the ones that could be at least partially parsed, along with a +// list of I/O and parse errors encountered. +// +// Because files are scanned in parallel, the token.Pos +// positions of the resulting ast.Files are not ordered. +// +func (ld *loader) parseFiles(filenames []string) ([]*ast.File, []error) { + var wg sync.WaitGroup + n := len(filenames) + parsed := make([]*ast.File, n) + errors := make([]error, n) + for i, file := range filenames { + wg.Add(1) + go func(i int, filename string) { + ioLimit <- true // wait + // ParseFile may return both an AST and an error. + parsed[i], errors[i] = ld.ParseFile(ld.Fset, filename) + <-ioLimit // signal + wg.Done() + }(i, file) + } + wg.Wait() + + // Eliminate nils, preserving order. + var o int + for _, f := range parsed { + if f != nil { + parsed[o] = f + o++ + } + } + parsed = parsed[:o] + + o = 0 + for _, err := range errors { + if err != nil { + errors[o] = err + o++ + } + } + errors = errors[:o] + + return parsed, errors +} + +// loadFromExportData returns type information for the specified +// package, loading it from an export data file on the first request. +func (ld *loader) loadFromExportData(lpkg *loaderPackage) (*types.Package, error) { + if lpkg.PkgPath == "" { + log.Fatalf("internal error: Package %s has no PkgPath", lpkg) + } + + // Because gcexportdata.Read has the potential to create or + // modify the types.Package for each node in the transitive + // closure of dependencies of lpkg, all exportdata operations + // must be sequential. (Finer-grained locking would require + // changes to the gcexportdata API.) + // + // The exportMu lock guards the Package.Pkg field and the + // types.Package it points to, for each Package in the graph. + // + // Not all accesses to Package.Pkg need to be protected by exportMu: + // graph ordering ensures that direct dependencies of source + // packages are fully loaded before the importer reads their Pkg field. + ld.exportMu.Lock() + defer ld.exportMu.Unlock() + + if tpkg := lpkg.Types; tpkg != nil && tpkg.Complete() { + return tpkg, nil // cache hit + } + + lpkg.IllTyped = true // fail safe + + if lpkg.ExportFile == "" { + // Errors while building export data will have been printed to stderr. + return nil, fmt.Errorf("no export data file") + } + f, err := os.Open(lpkg.ExportFile) + if err != nil { + return nil, err + } + defer f.Close() + + // Read gc export data. + // + // We don't currently support gccgo export data because all + // underlying workspaces use the gc toolchain. (Even build + // systems that support gccgo don't use it for workspace + // queries.) + r, err := gcexportdata.NewReader(f) + if err != nil { + return nil, fmt.Errorf("reading %s: %v", lpkg.ExportFile, err) + } + + // Build the view. + // + // The gcexportdata machinery has no concept of package ID. + // It identifies packages by their PkgPath, which although not + // globally unique is unique within the scope of one invocation + // of the linker, type-checker, or gcexportdata. + // + // So, we must build a PkgPath-keyed view of the global + // (conceptually ID-keyed) cache of packages and pass it to + // gcexportdata. The view must contain every existing + // package that might possibly be mentioned by the + // current package---its transitive closure. + // + // TODO(adonovan): it would be more simpler and more efficient + // if the export data machinery invoked a callback to + // get-or-create a package instead of a map. + // + view := make(map[string]*types.Package) // view seen by gcexportdata + seen := make(map[*loaderPackage]bool) // all visited packages + var visit func(pkgs map[string]*Package) + visit = func(pkgs map[string]*Package) { + for _, p := range pkgs { + lpkg := ld.pkgs[p.ID] + if !seen[lpkg] { + seen[lpkg] = true + view[lpkg.PkgPath] = lpkg.Types + visit(lpkg.Imports) + } + } + } + visit(lpkg.Imports) + + // Parse the export data. + // (May create/modify packages in view.) + tpkg, err := gcexportdata.Read(r, ld.Fset, view, lpkg.PkgPath) + if err != nil { + return nil, fmt.Errorf("reading %s: %v", lpkg.ExportFile, err) + } + + lpkg.Types = tpkg + lpkg.IllTyped = false + + return tpkg, nil +} + +func usesExportData(cfg *Config) bool { + return LoadTypes <= cfg.Mode && cfg.Mode < LoadAllSyntax +} |