With the improved escape sequence parser, it becomes easy to also improve

diagnostics.  Distinguish "incomplete escape sequence", "invalid special
character", and "unknown special character" from the generic "invalid
escape sequence", also promoting them from WARNING to ERROR because
incomplete escape sequences are severe syntax violations and because
encountering an invalid or unknown special character makes it likely
that part of the document content intended by the authors gets lost.

4 files changed, 26 insertions, 26 deletions

diff --git a/regress/char/accent/nocombine.out_lint b/regress/char/accent/nocombine.out_lint
index c9de4162..0f7be4d0 100644
--- a/regress/char/accent/nocombine.out_lint
+++ b/regress/char/accent/nocombine.out_lint
@@ -1,2 +1,2 @@
-mandoc: nocombine.in:8:27: WARNING: invalid escape sequence: \[']
-mandoc: nocombine.in:14:27: WARNING: invalid escape sequence: \[`]
+mandoc: nocombine.in:8:27: ERROR: invalid special character: \[']
+mandoc: nocombine.in:14:27: ERROR: invalid special character: \[`]
diff --git a/regress/char/space/invalid.out_lint b/regress/char/space/invalid.out_lint
index c05ef38f..4c146853 100644
--- a/regress/char/space/invalid.out_lint
+++ b/regress/char/space/invalid.out_lint
@@ -1,9 +1,9 @@
 mandoc: invalid.in:7:15: WARNING: invalid escape sequence: \[ 
-mandoc: invalid.in:8:14: WARNING: invalid escape sequence: \[%]
-mandoc: invalid.in:9:16: WARNING: invalid escape sequence: \[&]
-mandoc: invalid.in:10:12: WARNING: invalid escape sequence: \[:]
-mandoc: invalid.in:11:12: WARNING: invalid escape sequence: \[^]
-mandoc: invalid.in:12:16: WARNING: invalid escape sequence: \[_]
-mandoc: invalid.in:13:11: WARNING: invalid escape sequence: \[|]
-mandoc: invalid.in:14:12: WARNING: invalid escape sequence: \[~]
-mandoc: invalid.in:15:18: WARNING: invalid escape sequence: \[0]
+mandoc: invalid.in:8:14: ERROR: invalid special character: \[%]
+mandoc: invalid.in:9:16: ERROR: invalid special character: \[&]
+mandoc: invalid.in:10:12: ERROR: invalid special character: \[:]
+mandoc: invalid.in:11:12: ERROR: invalid special character: \[^]
+mandoc: invalid.in:12:16: ERROR: invalid special character: \[_]
+mandoc: invalid.in:13:11: ERROR: invalid special character: \[|]
+mandoc: invalid.in:14:12: ERROR: invalid special character: \[~]
+mandoc: invalid.in:15:18: ERROR: invalid special character: \[0]
diff --git a/regress/char/unicode/input.out_lint b/regress/char/unicode/input.out_lint
index 578a7704..fa36f876 100644
--- a/regress/char/unicode/input.out_lint
+++ b/regress/char/unicode/input.out_lint
@@ -24,11 +24,11 @@ mandoc: input.in:35:19: ERROR: skipping bad character: 0xbf
 mandoc: input.in:42:25: ERROR: skipping bad character: 0xed
 mandoc: input.in:42:26: ERROR: skipping bad character: 0xa0
 mandoc: input.in:42:27: ERROR: skipping bad character: 0x80
-mandoc: input.in:42:17: WARNING: invalid escape sequence: \[uD800]
+mandoc: input.in:42:17: ERROR: invalid special character: \[uD800]
 mandoc: input.in:43:25: ERROR: skipping bad character: 0xed
 mandoc: input.in:43:26: ERROR: skipping bad character: 0xbf
 mandoc: input.in:43:27: ERROR: skipping bad character: 0xbf
-mandoc: input.in:43:17: WARNING: invalid escape sequence: \[uDFFF]
+mandoc: input.in:43:17: ERROR: invalid special character: \[uDFFF]
 mandoc: input.in:53:19: ERROR: skipping bad character: 0xf0
 mandoc: input.in:53:20: ERROR: skipping bad character: 0x80
 mandoc: input.in:53:21: ERROR: skipping bad character: 0x80
@@ -57,25 +57,25 @@ mandoc: input.in:67:31: ERROR: skipping bad character: 0xf4
 mandoc: input.in:67:32: ERROR: skipping bad character: 0x90
 mandoc: input.in:67:33: ERROR: skipping bad character: 0x80
 mandoc: input.in:67:34: ERROR: skipping bad character: 0x80
-mandoc: input.in:67:21: WARNING: invalid escape sequence: \[u110000]
+mandoc: input.in:67:21: ERROR: invalid special character: \[u110000]
 mandoc: input.in:68:31: ERROR: skipping bad character: 0xf4
 mandoc: input.in:68:32: ERROR: skipping bad character: 0xbf
 mandoc: input.in:68:33: ERROR: skipping bad character: 0xbf
 mandoc: input.in:68:34: ERROR: skipping bad character: 0xbf
-mandoc: input.in:68:21: WARNING: invalid escape sequence: \[u13FFFF]
+mandoc: input.in:68:21: ERROR: invalid special character: \[u13FFFF]
 mandoc: input.in:69:31: ERROR: skipping bad character: 0xf5
 mandoc: input.in:69:32: ERROR: skipping bad character: 0x80
 mandoc: input.in:69:33: ERROR: skipping bad character: 0x80
 mandoc: input.in:69:34: ERROR: skipping bad character: 0x80
-mandoc: input.in:69:21: WARNING: invalid escape sequence: \[u140000]
+mandoc: input.in:69:21: ERROR: invalid special character: \[u140000]
 mandoc: input.in:70:31: ERROR: skipping bad character: 0xf7
 mandoc: input.in:70:32: ERROR: skipping bad character: 0xbf
 mandoc: input.in:70:33: ERROR: skipping bad character: 0xbf
 mandoc: input.in:70:34: ERROR: skipping bad character: 0xbf
-mandoc: input.in:70:21: WARNING: invalid escape sequence: \[u1FFFFF]
+mandoc: input.in:70:21: ERROR: invalid special character: \[u1FFFFF]
 mandoc: input.in:71:33: ERROR: skipping bad character: 0xf8
 mandoc: input.in:71:34: ERROR: skipping bad character: 0x88
 mandoc: input.in:71:35: ERROR: skipping bad character: 0x80
 mandoc: input.in:71:36: ERROR: skipping bad character: 0x80
 mandoc: input.in:71:37: ERROR: skipping bad character: 0x80
-mandoc: input.in:71:23: WARNING: invalid escape sequence: \[u200000]
+mandoc: input.in:71:23: ERROR: invalid special character: \[u200000]
diff --git a/regress/char/unicode/invalid.out_lint b/regress/char/unicode/invalid.out_lint
index ce9de988..0717605f 100644
--- a/regress/char/unicode/invalid.out_lint
+++ b/regress/char/unicode/invalid.out_lint
@@ -1,9 +1,9 @@
-mandoc: invalid.in:11:13: WARNING: invalid escape sequence: \[u2B]
-mandoc: invalid.in:11:20: WARNING: invalid escape sequence: \[u02B]
-mandoc: invalid.in:13:12: WARNING: invalid escape sequence: \[u0002B]
-mandoc: invalid.in:13:22: WARNING: invalid escape sequence: \[u00002B]
-mandoc: invalid.in:13:33: WARNING: invalid escape sequence: \[u000002B]
-mandoc: invalid.in:14:13: WARNING: invalid escape sequence: \[u110000]
-mandoc: invalid.in:14:24: WARNING: invalid escape sequence: \[u200000]
-mandoc: invalid.in:14:35: WARNING: invalid escape sequence: \[u1000000]
-mandoc: invalid.in:15:20: WARNING: invalid escape sequence: \[u1234g]
+mandoc: invalid.in:11:13: ERROR: unknown special character: \[u2B]
+mandoc: invalid.in:11:20: ERROR: unknown special character: \[u02B]
+mandoc: invalid.in:13:12: ERROR: invalid special character: \[u0002B]
+mandoc: invalid.in:13:22: ERROR: invalid special character: \[u00002B]
+mandoc: invalid.in:13:33: ERROR: unknown special character: \[u000002B]
+mandoc: invalid.in:14:13: ERROR: invalid special character: \[u110000]
+mandoc: invalid.in:14:24: ERROR: invalid special character: \[u200000]
+mandoc: invalid.in:14:35: ERROR: unknown special character: \[u1000000]
+mandoc: invalid.in:15:20: ERROR: unknown special character: \[u1234g]