feat: default fromPath for problem matchers

docs/adrs/0276-problem-matchers.md

@@ -250,6 +250,42 @@ Two problem matchers can be used:
 }
 ```
 
+#### Default from path
+
+The problem matcher can specify a `fromPath` property at the top level, which applies when a specific pattern doesn't provide a value for `fromPath`. This is useful for tools that don't include project file information in their output.
+
+For example, given the following compiler output that doesn't include project file information:
+
+```
+ClassLibrary.cs(16,24): warning CS0612: 'ClassLibrary.Helpers.MyHelper.Name' is obsolete
+```
+
+A problem matcher with a default from path can be used:
+
+```json
+{
+    "problemMatcher": [
+        {
+            "owner": "csc-minimal",
+            "fromPath": "ClassLibrary/ClassLibrary.csproj",
+            "pattern": [
+                {
+                    "regexp": "^(.+)\\((\\d+),(\\d+)\\): (error|warning) (.+): (.*)$",
+                    "file": 1,
+                    "line": 2,
+                    "column": 3,
+                    "severity": 4,
+                    "code": 5,
+                    "message": 6
+                }
+            ]
+        }
+    ]
+}
+```
+
+This ensures that the file is rooted to the correct path when there's not enough information in the error messages to extract a `fromPath`.
+
 #### Mitigate regular expression denial of service (ReDos)
 
 If a matcher exceeds a 1 second timeout when processing a line, retry up to two three times total.

src/Runner.Worker/IssueMatcher.cs

@@ -21,6 +21,7 @@ public MatcherChangedEventArgs(IssueMatcherConfig config)
     public sealed class IssueMatcher
     {
         private string _defaultSeverity;
+        private string _defaultFromPath;
         private string _owner;
         private IssuePattern[] _patterns;
         private IssueMatch[] _state;
@@ -29,6 +30,7 @@ public IssueMatcher(IssueMatcherConfig config, TimeSpan timeout)
         {
             _owner = config.Owner;
             _defaultSeverity = config.Severity;
+            _defaultFromPath = config.FromPath;
             _patterns = config.Patterns.Select(x => new IssuePattern(x, timeout)).ToArray();
             Reset();
         }
@@ -59,6 +61,19 @@ public string DefaultSeverity
             }
         }
 
+        public string DefaultFromPath
+        {
+            get
+            {
+                if (_defaultFromPath == null)
+                {
+                    _defaultFromPath = string.Empty;
+                }
+
+                return _defaultFromPath;
+            }
+        }
+
         public IssueMatch Match(string line)
         {
             // Single pattern
@@ -69,7 +84,7 @@ public IssueMatch Match(string line)
 
                 if (regexMatch.Success)
                 {
-                    return new IssueMatch(null, pattern, regexMatch.Groups, DefaultSeverity);
+                    return new IssueMatch(null, pattern, regexMatch.Groups, DefaultSeverity, DefaultFromPath);
                 }
 
                 return null;
@@ -110,7 +125,7 @@ public IssueMatch Match(string line)
                                 }
 
                                 // Return
-                                return new IssueMatch(runningMatch, pattern, regexMatch.Groups, DefaultSeverity);
+                                return new IssueMatch(runningMatch, pattern, regexMatch.Groups, DefaultSeverity, DefaultFromPath);
                             }
                             // Not the last pattern
                             else
@@ -184,7 +199,7 @@ public IssuePattern(IssuePatternConfig config, TimeSpan timeout)
 
     public sealed class IssueMatch
     {
-        public IssueMatch(IssueMatch runningMatch, IssuePattern pattern, GroupCollection groups, string defaultSeverity = null)
+        public IssueMatch(IssueMatch runningMatch, IssuePattern pattern, GroupCollection groups, string defaultSeverity = null, string defaultFromPath = null)
         {
             File = runningMatch?.File ?? GetValue(groups, pattern.File);
             Line = runningMatch?.Line ?? GetValue(groups, pattern.Line);
@@ -198,6 +213,11 @@ public IssueMatch(IssueMatch runningMatch, IssuePattern pattern, GroupCollection
             {
                 Severity = defaultSeverity;
             }
+
+            if (string.IsNullOrEmpty(FromPath) && !string.IsNullOrEmpty(defaultFromPath))
+            {
+                FromPath = defaultFromPath;
+            }
         }
 
         public string File { get; }
@@ -282,6 +302,9 @@ public sealed class IssueMatcherConfig
         [DataMember(Name = "pattern")]
         private IssuePatternConfig[] _patterns;
 
+        [DataMember(Name = "fromPath")]
+        private string _fromPath;
+
         public string Owner
         {
             get
@@ -318,6 +341,24 @@ public string Severity
             }
         }
 
+        public string FromPath
+        {
+            get
+            {
+                if (_fromPath == null)
+                {
+                    _fromPath = string.Empty;
+                }
+
+                return _fromPath;
+            }
+
+            set
+            {
+                _fromPath = value;
+            }
+        }
+
         public IssuePatternConfig[] Patterns
         {
             get

src/Test/L0/Worker/IssueMatcherL0.cs

@@ -896,5 +896,173 @@ public void Matcher_SinglePattern_ExtractsProperties()
             Assert.Equal("not-working", match.Message);
             Assert.Equal("my-project.proj", match.FromPath);
         }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public void Matcher_SinglePattern_DefaultFromPath()
+        {
+            var config = JsonUtility.FromString<IssueMatchersConfig>(@"
+{
+  ""problemMatcher"": [
+    {
+      ""owner"": ""myMatcher"",
+      ""fromPath"": ""subdir/default-project.csproj"",
+      ""pattern"": [
+        {
+          ""regexp"": ""^file:(.+) line:(.+) column:(.+) severity:(.+) code:(.+) message:(.+)$"",
+          ""file"": 1,
+          ""line"": 2,
+          ""column"": 3,
+          ""severity"": 4,
+          ""code"": 5,
+          ""message"": 6
+        }
+      ]
+    }
+  ]
+}
+");
+            config.Validate();
+            var matcher = new IssueMatcher(config.Matchers[0], TimeSpan.FromSeconds(1));
+
+            var match = matcher.Match("file:my-file.cs line:123 column:45 severity:real-bad code:uh-oh message:not-working");
+            Assert.Equal("my-file.cs", match.File);
+            Assert.Equal("123", match.Line);
+            Assert.Equal("45", match.Column);
+            Assert.Equal("real-bad", match.Severity);
+            Assert.Equal("uh-oh", match.Code);
+            Assert.Equal("not-working", match.Message);
+            Assert.Equal("subdir/default-project.csproj", match.FromPath);
+
+            // Test that a pattern-specific fromPath overrides the default
+            config = JsonUtility.FromString<IssueMatchersConfig>(@"
+{
+  ""problemMatcher"": [
+    {
+      ""owner"": ""myMatcher"",
+      ""fromPath"": ""subdir/default-project.csproj"",
+      ""pattern"": [
+        {
+          ""regexp"": ""^file:(.+) line:(.+) column:(.+) severity:(.+) code:(.+) message:(.+) fromPath:(.+)$"",
+          ""file"": 1,
+          ""line"": 2,
+          ""column"": 3,
+          ""severity"": 4,
+          ""code"": 5,
+          ""message"": 6,
+          ""fromPath"": 7
+        }
+      ]
+    }
+  ]
+}
+");
+            config.Validate();
+            matcher = new IssueMatcher(config.Matchers[0], TimeSpan.FromSeconds(1));
+
+            match = matcher.Match("file:my-file.cs line:123 column:45 severity:real-bad code:uh-oh message:not-working fromPath:my-project.proj");
+            Assert.Equal("my-file.cs", match.File);
+            Assert.Equal("123", match.Line);
+            Assert.Equal("45", match.Column);
+            Assert.Equal("real-bad", match.Severity);
+            Assert.Equal("uh-oh", match.Code);
+            Assert.Equal("not-working", match.Message);
+            Assert.Equal("my-project.proj", match.FromPath);
+        }
+
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public void Matcher_MultiplePatterns_DefaultFromPath()
+        {
+            var config = JsonUtility.FromString<IssueMatchersConfig>(@"
+{
+  ""problemMatcher"": [
+    {
+      ""owner"": ""myMatcher"",
+      ""fromPath"": ""subdir/default-project.csproj"",
+      ""pattern"": [
+        {
+          ""regexp"": ""^file:(.+)$"",
+          ""file"": 1,
+        },
+        {
+          ""regexp"": ""^severity:(.+)$"",
+          ""severity"": 1
+        },
+        {
+          ""regexp"": ""^line:(.+) column:(.+) code:(.+) message:(.+)$"",
+          ""line"": 1,
+          ""column"": 2,
+          ""code"": 3,
+          ""message"": 4
+        }
+      ]
+    }
+  ]
+}
+");
+            config.Validate();
+            var matcher = new IssueMatcher(config.Matchers[0], TimeSpan.FromSeconds(1));
+
+            var match = matcher.Match("file:my-file.cs");
+            Assert.Null(match);
+            match = matcher.Match("severity:real-bad");
+            Assert.Null(match);
+            match = matcher.Match("line:123 column:45 code:uh-oh message:not-working");
+            Assert.Equal("my-file.cs", match.File);
+            Assert.Equal("123", match.Line);
+            Assert.Equal("45", match.Column);
+            Assert.Equal("real-bad", match.Severity);
+            Assert.Equal("uh-oh", match.Code);
+            Assert.Equal("not-working", match.Message);
+            Assert.Equal("subdir/default-project.csproj", match.FromPath);
+
+            // Test that pattern-specific fromPath overrides the default
+            config = JsonUtility.FromString<IssueMatchersConfig>(@"
+{
+  ""problemMatcher"": [
+    {
+      ""owner"": ""myMatcher"",
+      ""fromPath"": ""subdir/default-project.csproj"",
+      ""pattern"": [
+        {
+          ""regexp"": ""^file:(.+) fromPath:(.+)$"",
+          ""file"": 1,
+          ""fromPath"": 2
+        },
+        {
+          ""regexp"": ""^severity:(.+)$"",
+          ""severity"": 1
+        },
+        {
+          ""regexp"": ""^line:(.+) column:(.+) code:(.+) message:(.+)$"",
+          ""line"": 1,
+          ""column"": 2,
+          ""code"": 3,
+          ""message"": 4
+        }
+      ]
+    }
+  ]
+}
+");
+            config.Validate();
+            matcher = new IssueMatcher(config.Matchers[0], TimeSpan.FromSeconds(1));
+
+            match = matcher.Match("file:my-file.cs fromPath:my-project.proj");
+            Assert.Null(match);
+            match = matcher.Match("severity:real-bad");
+            Assert.Null(match);
+            match = matcher.Match("line:123 column:45 code:uh-oh message:not-working");
+            Assert.Equal("my-file.cs", match.File);
+            Assert.Equal("123", match.Line);
+            Assert.Equal("45", match.Column);
+            Assert.Equal("real-bad", match.Severity);
+            Assert.Equal("uh-oh", match.Code);
+            Assert.Equal("not-working", match.Message);
+            Assert.Equal("my-project.proj", match.FromPath);
+        }
     }
 }

src/Test/L0/Worker/OutputManagerL0.cs

@@ -937,6 +937,62 @@ public async void MatcherFromPath()
             }
         }
 
+        [Fact]
+        [Trait("Level", "L0")]
+        [Trait("Category", "Worker")]
+        public async void MatcherDefaultFromPath()
+        {
+            var matchers = new IssueMatchersConfig
+            {
+                Matchers =
+                {
+                    new IssueMatcherConfig
+                    {
+                        Owner = "my-matcher-1",
+                        FromPath = "workflow-repo/some-project/some-project.proj",
+                        Patterns = new[]
+                        {
+                            new IssuePatternConfig
+                            {
+                                Pattern = @"(.+): (.+)",
+                                File = 1,
+                                Message = 2,
+                            },
+                        },
+                    },
+                },
+            };
+            using (var hostContext = Setup(matchers: matchers))
+            using (_outputManager)
+            {
+                // Setup github.workspace, github.repository
+                var workDirectory = hostContext.GetDirectory(WellKnownDirectory.Work);
+                ArgUtil.NotNullOrEmpty(workDirectory, nameof(workDirectory));
+                Directory.CreateDirectory(workDirectory);
+                var workspaceDirectory = Path.Combine(workDirectory, "workspace");
+                Directory.CreateDirectory(workspaceDirectory);
+                _executionContext.Setup(x => x.GetGitHubContext("workspace")).Returns(workspaceDirectory);
+                _executionContext.Setup(x => x.GetGitHubContext("repository")).Returns("my-org/workflow-repo");
+
+                // Setup a git repository
+                var repositoryPath = Path.Combine(workspaceDirectory, "workflow-repo");
+                await CreateRepository(hostContext, repositoryPath, "https://github.com/my-org/workflow-repo");
+
+                // Create a test file
+                var filePath = Path.Combine(repositoryPath, "some-project", "some-directory", "some-file.txt");
+                Directory.CreateDirectory(Path.GetDirectoryName(filePath));
+                File.WriteAllText(filePath, "");
+
+                // Process
+                Process("some-directory/some-file.txt: some error");
+                Assert.Equal(1, _issues.Count);
+                Assert.Equal("some error", _issues[0].Item1.Message);
+                Assert.Equal("some-project/some-directory/some-file.txt", _issues[0].Item1.Data["file"]);
+                Assert.Equal(0, _commands.Count);
+                Assert.Equal(0, _messages.Count);
+            }
+        }
+
         [Fact]
         [Trait("Level", "L0")]
         [Trait("Category", "Worker")]