Go: Remove auto-generated go.mod files when done

Author: mbg

go/extractor/autobuilder/build-environment.go

@@ -269,6 +269,9 @@ func IdentifyEnvironment() {
 	var v versionInfo
 	workspaces := project.GetWorkspaceInfo(false)
 
+	// Remove temporary extractor files (e.g. auto-generated go.mod files) when we are done
+	defer project.RemoveTemporaryExtractorFiles()
+
 	// Find the greatest Go version required by any of the workspaces.
 	greatestGoVersion := project.GoVersionInfo{Version: "", Found: false}
 	for _, workspace := range workspaces {

go/extractor/cli/go-autobuilder/go-autobuilder.go

@@ -526,6 +526,9 @@ func installDependenciesAndBuild() {
 		os.Setenv("GO111MODULE", "auto")
 	}
 
+	// Remove temporary extractor files (e.g. auto-generated go.mod files) when we are done
+	defer project.RemoveTemporaryExtractorFiles()
+
 	for _, workspace := range workspaces {
 		goVersionInfo := workspace.RequiredGoVersion()
 

go/extractor/project/project.go

@@ -109,9 +109,12 @@ func checkDirsNested(inputDirs []string) (string, bool) {
 	return dirs[0], true
 }
 
+// A list of files we created that should be removed after we are done.
+var filesToRemove []string
+
 // Try to initialize a go.mod file for projects that do not already have one.
 func initGoModForLegacyProject(path string) {
-	log.Printf("Project appears to be a legacy Go project, attempting to initialize go.mod")
+	log.Printf("Project appears to be a legacy Go project, attempting to initialize go.mod in %s\n", path)
 
 	modInit := toolchain.InitModule(path)
 
@@ -120,6 +123,9 @@ func initGoModForLegacyProject(path string) {
 		return
 	}
 
+	// Add the go.mod file to a list of files we should remove later.
+	filesToRemove = append(filesToRemove, filepath.Join(path, "go.mod"))
+
 	modTidy := toolchain.TidyModule(path)
 	out, err := modTidy.CombinedOutput()
 	log.Println(string(out))
@@ -133,6 +139,18 @@ func initGoModForLegacyProject(path string) {
 	}
 }
 
+// Attempts to remove all files that we created.
+func RemoveTemporaryExtractorFiles() {
+	for _, path := range filesToRemove {
+		err := os.Remove(path)
+		if err != nil {
+			log.Printf("Unable to remove file we created at %s: %s\n", path, err.Error())
+		}
+	}
+
+	filesToRemove = nil
+}
+
 // Find all go.work files in the working directory and its subdirectories
 func findGoWorkFiles() []string {
 	return util.FindAllFilesWithName(".", "go.work", "vendor")