lib9p: idl.gen: Have pretty and informative error messages

"Ignore space change" will be useful when viewing this diff.

1 files changed, 24 insertions, 1 deletions

diff --git a/lib9p/idl.gen b/lib9p/idl.gen
index b23b5b8..558592f 100755
--- a/lib9p/idl.gen
+++ b/lib9p/idl.gen
@@ -855,11 +855,34 @@ LM_FLATTEN bool _{idprefix}stat_marshal(struct _marshal_ctx *ctx, struct lib9p_s
 if __name__ == "__main__":
     import sys
 
+    if typing.TYPE_CHECKING:
+
+        class ANSIColors:
+            MAGENTA = "\x1b[35m"
+            RED = "\x1b[31m"
+            RESET = "\x1b[0m"
+
+    else:
+        from _colorize import ANSIColors  # Present in Python 3.13+
+
     if len(sys.argv) < 2:
         raise ValueError("requires at least 1 .9p filename")
     parser = idl.Parser()
     for txtname in sys.argv[1:]:
-        parser.parse_file(txtname)
+        try:
+            parser.parse_file(txtname)
+        except SyntaxError as e:
+            print(
+                f"{ANSIColors.RED}{e.filename}{ANSIColors.RESET}:{ANSIColors.MAGENTA}{e.lineno}{ANSIColors.RESET}: {e.msg}",
+                file=sys.stderr,
+            )
+            assert e.text
+            print(f"\t{e.text}", file=sys.stderr)
+            print(
+                f"\t{ANSIColors.RED}{'~'*len(e.text)}{ANSIColors.RESET}",
+                file=sys.stderr,
+            )
+            sys.exit(2)
     versions, typs = parser.all()
     outdir = os.path.normpath(os.path.join(sys.argv[0], ".."))
     with open(os.path.join(outdir, "include/lib9p/9p.generated.h"), "w") as fh: