SERVER-112866 suggest valid targets if bazel test +blah doesn't match anything (#42990)

GitOrigin-RevId: 62ce070cb6884e8da5b7a29875536cb7e244e7bd

bazel/wrapper_hook/plus_interface.py

@@ -1,3 +1,4 @@
+import difflib
 import os
 import pathlib
 import platform
@@ -183,7 +184,20 @@ def test_runner_interface(
                     ):
                         bin_targets.append(bin_target)
                         real_target = bin_target
-                replacements[arg] = [real_target]
+                if not real_target:
+                    # Target not found - suggest similar ones and pass through
+                    suggestions = difflib.get_close_matches(test_name, sources_to_bin.keys(), n=5)
+                    error_msg = f"WARNING: Target '{arg}' not found"
+                    if suggestions:
+                        error_msg += "\n\nDid you mean one of these?\n"
+                        for suggestion in suggestions:
+                            error_msg += f"  +{suggestion}\n"
+                    else:
+                        error_msg += " and no similar targets."
+                    print(error_msg, file=sys.stderr)
+                    # Pass through the argument unchanged: it might be an important argument
+                else:
+                    replacements[arg] = [real_target]
             else:
                 # defer source targets to see if we can skip redundant tests
                 source_targets[test_name] = [arg, real_target]

buildscripts/tests/test_bazel_plus_test_interface.py

@@ -1,5 +1,7 @@
 import sys
 import unittest
+from contextlib import redirect_stderr
+from io import StringIO
 
 sys.path.append(".")
 
@@ -10,6 +12,23 @@ from bazel.wrapper_hook.plus_interface import (
 )
 
 
+def validate_first_suggestion(stderr_output: str, expected_suggestion: str):
+    assert (
+        "Did you mean one of these?" in stderr_output
+    ), f"Expected 'Did you mean one of these?' in stderr, got: {stderr_output}"
+
+    suggestion_section = stderr_output.split("Did you mean one of these?")[1]
+    first_suggestion_line = [
+        line.strip()
+        for line in suggestion_section.split("\n")
+        if line.strip() and line.strip().startswith("+")
+    ][0]
+
+    assert (
+        first_suggestion_line == expected_suggestion
+    ), f"Expected first suggestion to be '{expected_suggestion}', got '{first_suggestion_line}'"
+
+
 class Tests(unittest.TestCase):
     def test_single_source_file(self):
         def buildozer_output(autocomplete_query):
@@ -80,7 +99,9 @@ class Tests(unittest.TestCase):
             "+some_feature",
         ]
 
-        result = test_runner_interface(args, False, buildozer_output)
+        stderr_capture = StringIO()
+        with redirect_stderr(stderr_capture):
+            result = test_runner_interface(args, False, buildozer_output)
 
         assert result == [
             "test",
@@ -92,6 +113,10 @@ class Tests(unittest.TestCase):
             "--test_arg=source1|source2",
         ]
 
+        # Verify that the warning for +some_feature was captured
+        stderr_output = stderr_capture.getvalue()
+        assert "WARNING: Target '+some_feature' not found" in stderr_output
+
     def test_single_bin_file(self):
         def buildozer_output(autocomplete_query):
             return "//some:test [source1.cpp source2.cpp]"
@@ -185,7 +210,9 @@ class Tests(unittest.TestCase):
 
         args = ["wrapper_hook", "test", "+source1", "+source2", "+source3", "+source4"]
 
-        result = test_runner_interface(args, False, buildozer_output)
+        stderr_capture = StringIO()
+        with redirect_stderr(stderr_capture):
+            result = test_runner_interface(args, False, buildozer_output)
 
         assert result == [
             "test",
@@ -195,6 +222,10 @@ class Tests(unittest.TestCase):
             "--test_arg=source1|source3|source4",
         ]
 
+        # Verify that the warning for +source2 was captured
+        stderr_output = stderr_capture.getvalue()
+        assert "WARNING: Target '+source2' not found" in stderr_output
+
     def test_prefixes(self):
         def buildozer_output(autocomplete_query):
             return "//some:test [source1.cpp source2.cpp source3.cpp s+ource4.cpp]"
@@ -210,6 +241,64 @@ class Tests(unittest.TestCase):
             "--test_arg=source1|source2|source3",
         ]
 
+    def test_target_not_found_with_suggestions(self):
+        """Test that unrecognized targets pass through unchanged (not a test target)."""
+
+        def buildozer_output(autocomplete_query):
+            return "//some:test [bson_obj_test.cpp bson_element_test.cpp other_test.cpp]"
+
+        args = ["wrapper_hook", "test", "+bsonobj_test"]  # Typo: missing underscore
+
+        stderr_capture = StringIO()
+        with redirect_stderr(stderr_capture):
+            result = test_runner_interface(args, False, buildozer_output)
+
+        # Should pass through unchanged since it's not a recognized target
+        assert result == ["test", "+bsonobj_test"]
+
+        # Check that suggestions were printed
+        stderr_output = stderr_capture.getvalue()
+        validate_first_suggestion(stderr_output, "+bson_obj_test")
+
+    def test_target_not_found_no_close_matches(self):
+        """Test that completely unrecognized targets pass through unchanged."""
+
+        def buildozer_output(autocomplete_query):
+            return "//some:test [bson_obj_test.cpp other_test.cpp]"
+
+        args = ["wrapper_hook", "test", "+xyz123"]  # Completely different target
+
+        stderr_capture = StringIO()
+        with redirect_stderr(stderr_capture):
+            result = test_runner_interface(args, False, buildozer_output)
+
+        # Should pass through unchanged
+        assert result == ["test", "+xyz123"]
+
+        # Check that "no similar targets" message was printed
+        stderr_output = stderr_capture.getvalue()
+        assert (
+            "and no similar targets" in stderr_output
+        ), f"Expected 'and no similar targets' in stderr output, got: {stderr_output}"
+
+    def test_target_not_found_partial_match(self):
+        """Test that partial matches still pass through when not found."""
+
+        def buildozer_output(autocomplete_query):
+            return "//some:test [bson_obj_test.cpp bson_element_test.cpp bson_utf8_test.cpp]"
+
+        args = ["wrapper_hook", "test", "+bson_obj"]  # Missing '_test' suffix
+
+        stderr_capture = StringIO()
+        with redirect_stderr(stderr_capture):
+            result = test_runner_interface(args, False, buildozer_output)
+
+        # Should pass through unchanged
+        assert result == ["test", "+bson_obj"]
+
+        stderr_output = stderr_capture.getvalue()
+        validate_first_suggestion(stderr_output, "+bson_obj_test")
+
 
 if __name__ == "__main__":
     unittest.main()