Merge pull request #755 from calumgrant/cs/extractor-alerts

C#: Fix some LGTM alerts on the extractor

Author: hvitved

csharp/autobuilder/Semmle.Autobuild/Project.cs

@@ -39,7 +39,7 @@ public Project(Autobuilder builder, string path) : base(builder, path)
             {
                 projFile = builder.Actions.LoadXml(FullPath);
             }
-            catch (Exception e) when (e is XmlException || e is FileNotFoundException)
+            catch (Exception ex) when (ex is XmlException || ex is FileNotFoundException)
             {
                 builder.Log(Severity.Info, $"Unable to read project file {path}.");
                 return;

csharp/autobuilder/Semmle.Autobuild/Solution.cs

@@ -63,7 +63,7 @@ public Solution(Autobuilder builder, string path, bool allowProject) : base(buil
             {
                 solution = SolutionFile.Parse(FullPath);
             }
-            catch (Exception e) when (e is InvalidProjectFileException || e is FileNotFoundException)
+            catch (Exception ex) when (ex is InvalidProjectFileException || ex is FileNotFoundException)
             {
                 // We allow specifying projects as solutions in lgtm.yml, so model
                 // that scenario as a solution with just that one project

csharp/extractor/Semmle.Extraction.CIL/Entities/Assembly.cs

@@ -143,7 +143,7 @@ public static void ExtractCIL(Layout layout, string assemblyPath, ILogger logger
                     }
                 }
             }
-            catch (Exception ex)
+            catch (Exception ex)  // lgtm[cs/catch-of-all-exceptions]
             {
                 logger.Log(Severity.Error, string.Format("Exception extracting {0}: {1}", assemblyPath, ex));
             }

csharp/extractor/Semmle.Extraction.CIL/Entities/Method.cs

@@ -402,6 +402,9 @@ public MemberReferenceMethod(GenericContext gc, MemberReferenceHandle handle) :
 
             declType = parentMethod == null ? parent as Type : parentMethod.DeclaringType;
 
+            if (declType is null)
+                throw new InternalError("Parent context of method is not a type");
+
             ShortId = MakeMethodId(declType, nameLabel);
 
             var typeSourceDeclaration = declType.SourceDeclaration;

csharp/extractor/Semmle.Extraction.CIL/Entities/Type.cs

@@ -1121,7 +1121,7 @@ class GenericMethodParameter : ITypeSignature
             static readonly Id excl = Id.Create("M!");
             public Id MakeId(GenericContext outerGc)
             {
-                if (innerGc != outerGc && innerGc is Method method)
+                if (!ReferenceEquals(innerGc, outerGc) && innerGc is Method method)
                     return open + method.Label.Value + close + excl + index;
                 return excl + index;
             }

csharp/extractor/Semmle.Extraction.CSharp.Standalone/BuildAnalysis.cs

@@ -283,7 +283,7 @@ void AnalyseProjectFiles(FileInfo[] projectFiles)
                     }
                     ++succeededProjects;
                 }
-                catch (Exception ex)
+                catch (Exception ex)  // lgtm[cs/catch-of-all-exceptions]
                 {
                     ++failedProjects;
                     progressMonitor.FailedProjectFile(proj.FullName, ex.Message);

csharp/extractor/Semmle.Extraction.CSharp.Standalone/NugetPackages.cs

@@ -183,10 +183,10 @@ void RestoreNugetPackage(string package, IProgressMonitor pm)
                     }
                 }
             }
-            catch (Exception e)
-                when (e is System.ComponentModel.Win32Exception || e is FileNotFoundException)
+            catch (Exception ex)
+                when (ex is System.ComponentModel.Win32Exception || ex is FileNotFoundException)
             {
-                pm.FailedNugetCommand(pi.FileName, pi.Arguments, e.Message);
+                pm.FailedNugetCommand(pi.FileName, pi.Arguments, ex.Message);
             }
         }
 

csharp/extractor/Semmle.Extraction.CSharp/Analyser.cs

@@ -97,7 +97,7 @@ void SetReferencePaths()
                         extractor.SetAssemblyFile(assemblyIdentity, refPath);
                     }
                 }
-                catch (Exception ex)
+                catch (Exception ex)  // lgtm[cs/catch-of-all-exceptions]
                 {
                     extractor.Message(new Message
                     {
@@ -272,7 +272,7 @@ void DoAnalyseAssembly(PortableExecutableReference r)
                     ReportProgress(assemblyPath, trapWriter.TrapFile, stopwatch.Elapsed, skipExtraction ? AnalysisAction.UpToDate : AnalysisAction.Extracted);
                 }
             }
-            catch (Exception ex)
+            catch (Exception ex)  // lgtm[cs/catch-of-all-exceptions]
             {
                 Logger.Log(Severity.Error, "  Unhandled exception analyzing {0}: {1}", r.FilePath, ex);
             }
@@ -354,7 +354,7 @@ void DoExtractTree(SyntaxTree tree)
 
                 ReportProgress(sourcePath, trapPath, stopwatch.Elapsed, excluded ? AnalysisAction.Excluded : upToDate ? AnalysisAction.UpToDate : AnalysisAction.Extracted);
             }
-            catch (Exception ex)
+            catch (Exception ex)  // lgtm[cs/catch-of-all-exceptions]
             {
                 extractor.Message(new Message { exception = ex, message = string.Format("Unhandled exception processing {0}: {1}", tree.FilePath, ex), severity = Severity.Error });
             }

csharp/extractor/Semmle.Extraction.CSharp/Entities/Modifier.cs

@@ -134,6 +134,9 @@ public static void ExtractModifiers(Context cx, IEntity key, ISymbol symbol)
             if (symbol.Kind == SymbolKind.NamedType)
             {
                 INamedTypeSymbol nt = symbol as INamedTypeSymbol;
+                if (nt is null)
+                    throw new InternalError(symbol, "Symbol kind is inconsistent with its type");
+
                 if (nt.TypeKind == TypeKind.Struct)
                 {
                     // Sadly, these properties are internal so cannot be accessed directly.

csharp/extractor/Semmle.Extraction.CSharp/Entities/Statements/Checked.cs

@@ -1,4 +1,4 @@
-using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.CSharp.Syntax;  // lgtm[cs/similar-file]
 using Semmle.Extraction.Kinds;
 
 namespace Semmle.Extraction.CSharp.Entities.Statements