Pretty print error messages

Author: virtuald

src/semiwrap/hooks.py

@@ -1,6 +1,9 @@
 # TODO: rename this
 
+import os
 import pathlib
+import sys
+import traceback
 import typing as T
 
 from hatchling.plugin import hookimpl
@@ -52,9 +55,45 @@ def initialize(self, version: str, build_data: T.Dict[str, T.Any]) -> None:
         trampoline_build_path = stage0_build_path / "trampolines"
         trampoline_meson_build = trampoline_build_path / "meson.build"
 
-        eps = gen_meson_to_file(
-            project_root, stage0_meson_build, stage1_meson_build, trampoline_meson_build
-        )
+        try:
+            eps = gen_meson_to_file(
+                project_root,
+                stage0_meson_build,
+                stage1_meson_build,
+                trampoline_meson_build,
+            )
+        except Exception as e:
+            # Reading the stack trace is annoying, most of the time the exception content
+            # is enough to figure out what you did wrong.
+            if os.environ.get("SEMIWRAP_ERROR_VERBOSE") == "1":
+                raise
+
+            msg = [
+                "ERROR: exception occurred when processing `pyproject.toml`",
+                "",
+            ]
+
+            msg += traceback.format_exception_only(e, show_group=True)
+            cause = e.__context__
+            while cause is not None:
+                if "prepare_metadata_for_build_editable" in str(cause):
+                    break
+
+                el = traceback.format_exception_only(cause, show_group=True)
+                el[0] = f"- caused by {el[0]}"
+                msg += el
+
+                if cause.__suppress_context__:
+                    break
+
+                cause = cause.__context__
+
+            msg.append(
+                "Set environment variable SEMIWRAP_ERROR_VERBOSE=1 for stacktrace"
+            )
+
+            print("\n".join(msg), file=sys.stderr)
+            sys.exit(1)
 
         if eps:
             # .. not documented but it works?