Keep path in invalid project exceptions (#1287)

When #1004 moved the standard XML reading approach to be stream-based
rather than file-based, the exceptions thrown on malformed XML
changed--System.Xml no longer knows the path, so it isn't included in the
XmlException. That caused MSBuild to fail to report the location of the
XML error in a nice way as it had done before.

Almost every case where we constructed a BuildEventFileInfo object already
had access to the full path, so I added a constructor that accepted that
as an argument and overrides the possibly-empty path returned from
XmlException.SourceUri.

Added a unit test to verify that the information is indeed preserved in the exception.

Fixes #1286.

src/Shared/BuildEventFileInfo.cs

@@ -97,6 +97,16 @@ internal BuildEventFileInfo(XmlException e)
             _endColumn = 0;
         }
 
+        /// <summary>
+        /// Creates an instance of this class using the information in the given XmlException and file location.
+        /// </summary>
+        internal BuildEventFileInfo(string file, XmlException e) : this(e)
+        {
+            ErrorUtilities.VerifyThrowArgumentNull(file, nameof(file));
+
+            _file = file;
+        }
+
         #endregion
 
         #region Properties

src/XMakeBuildEngine/Construction/ProjectRootElement.cs

@@ -2059,7 +2059,7 @@ private XmlDocumentWithLocation LoadDocument(string fullPath, bool preserveForma
 
                     if (xmlException != null)
                     {
-                        fileInfo = new BuildEventFileInfo(xmlException);
+                        fileInfo = new BuildEventFileInfo(fullPath, xmlException);
                     }
                     else
                     {

src/XMakeBuildEngine/Definition/Toolset.cs

@@ -1046,7 +1046,7 @@ private void LoadAndRegisterFromTasksFile(string searchPath, string[] defaultTas
                 catch (XmlException e)
                 {
                     // handle XML errors in the default tasks file
-                    ProjectFileErrorUtilities.VerifyThrowInvalidProjectFile(false, new BuildEventFileInfo(e), taskFileError, e.Message);
+                    ProjectFileErrorUtilities.VerifyThrowInvalidProjectFile(false, new BuildEventFileInfo(defaultTasksFile, e), taskFileError, e.Message);
                 }
                 catch (Exception e) when (ExceptionHandling.IsIoRelatedException(e))
                 {

src/XMakeBuildEngine/UnitTests/InvalidProjectFileException_Tests.cs

@@ -82,5 +82,36 @@ public void ErrorCodeShouldAppearForCircularDependency()
                 File.Delete(file);
             }
         }
+
+        /// <summary>
+        /// Regression test for https://github.com/Microsoft/msbuild/issues/1286
+        /// </summary>
+        [Fact]
+        public void LogErrorShouldHavePathAndLocation()
+        {
+            string file = Path.GetTempPath() + Guid.NewGuid().ToString("N");
+
+            try
+            {
+                File.WriteAllText(file, ObjectModelHelpers.CleanupFileContents(@"
+                    <Project ToolsVersion='msbuilddefaulttoolsversion' xmlns='msbuildnamespace'>
+                        <Target Name=[invalid] />
+                    </Project>"));
+
+                var _ = ObjectModelHelpers.BuildTempProjectFileExpectFailure(file);
+
+                Assert.True(false, "Loading an invalid project should have thrown an InvalidProjectFileException.");
+            }
+            catch (InvalidProjectFileException e)
+            {
+                Assert.Equal(3, e.LineNumber);
+                Assert.Equal(38, e.ColumnNumber);
+                Assert.Equal(file, e.ProjectFile); // https://github.com/Microsoft/msbuild/issues/1286
+            }
+            finally
+            {
+                File.Delete(file);
+            }
+        }
     }
 }