From 51daeb3229e488ce4a57d16bcfd77b6de896d03c Mon Sep 17 00:00:00 2001
From: Tsuyoshi Hombashi <tsuyoshi.hombashi@gmail.com>
Date: Thu, 1 Jul 2021 20:10:51 +0900
Subject: [PATCH] Modify jsonnet-lint to accept multiple input files (#545)

Modify jsonnet-lint to accept multiple input files
---
 cmd/jsonnet-lint/cmd.go | 46 ++++++++++++--------------
 linter/linter.go        | 73 ++++++++++++++++++++++++++---------------
 linter/linter_test.go   | 40 +++++++++++++++++++++-
 3 files changed, 106 insertions(+), 53 deletions(-)

diff --git a/cmd/jsonnet-lint/cmd.go b/cmd/jsonnet-lint/cmd.go
index ea2313b4e..3c6cd426b 100644
--- a/cmd/jsonnet-lint/cmd.go
+++ b/cmd/jsonnet-lint/cmd.go
@@ -21,7 +21,7 @@ func version(o io.Writer) {
 func usage(o io.Writer) {
 	version(o)
 	fmt.Fprintln(o)
-	fmt.Fprintln(o, "jsonnet-lint {<option>} { <filename> }")
+	fmt.Fprintln(o, "jsonnet-lint {<option>} { <filenames ...> }")
 	fmt.Fprintln(o)
 	fmt.Fprintln(o, "Available options:")
 	fmt.Fprintln(o, "  -h / --help                This message")
@@ -53,8 +53,8 @@ func usage(o io.Writer) {
 
 type config struct {
 	// TODO(sbarzowski) Allow multiple root files checked at once for greater efficiency
-	inputFile string
-	evalJpath []string
+	inputFiles []string
+	evalJpath  []string
 }
 
 func makeConfig() config {
@@ -112,11 +112,7 @@ func processArgs(givenArgs []string, config *config, vm *jsonnet.VM) (processArg
 		return processArgsStatusFailureUsage, fmt.Errorf("file not provided")
 	}
 
-	if len(remainingArgs) > 1 {
-		return processArgsStatusFailure, fmt.Errorf("only one file is allowed")
-	}
-
-	config.inputFile = remainingArgs[0]
+	config.inputFiles = remainingArgs
 	return processArgsStatusContinue, nil
 }
 
@@ -164,27 +160,27 @@ func main() {
 		JPaths: config.evalJpath,
 	})
 
-	inputFile, err := os.Open(config.inputFile)
-	if err != nil {
-		die(err)
-	}
-	data, err := ioutil.ReadAll(inputFile)
-	if err != nil {
-		die(err)
-	}
-	err = inputFile.Close()
-	if err != nil {
-		die(err)
+	var snippets []linter.Snippet
+	for _, inputFile := range config.inputFiles {
+		f, err := os.Open(inputFile)
+		if err != nil {
+			die(err)
+		}
+		data, err := ioutil.ReadAll(f)
+		if err != nil {
+			die(err)
+		}
+		err = f.Close()
+		if err != nil {
+			die(err)
+		}
+
+		snippets = append(snippets, linter.Snippet{FileName: inputFile, Code: string(data)})
 	}
 
 	cmd.MemProfile()
 
-	_, err = jsonnet.SnippetToAST(config.inputFile, string(data))
-	if err != nil {
-		die(err)
-	}
-
-	errorsFound := linter.LintSnippet(vm, os.Stderr, config.inputFile, string(data))
+	errorsFound := linter.LintSnippet(vm, os.Stderr, snippets)
 	if errorsFound {
 		fmt.Fprintf(os.Stderr, "Problems found!\n")
 		os.Exit(2)
diff --git a/linter/linter.go b/linter/linter.go
index 7154dfa1c..7092764c3 100644
--- a/linter/linter.go
+++ b/linter/linter.go
@@ -22,6 +22,12 @@ type ErrorWriter struct {
 	Writer      io.Writer
 }
 
+// Snippet represents a jsonnet file data that to be linted
+type Snippet struct {
+	FileName string
+	Code     string
+}
+
 func (e *ErrorWriter) writeError(vm *jsonnet.VM, err errors.StaticError) {
 	e.ErrorsFound = true
 	_, writeErr := e.Writer.Write([]byte(vm.ErrorFormatter.Format(err) + "\n"))
@@ -38,10 +44,14 @@ type nodeWithLocation struct {
 }
 
 // Lint analyses a node and reports any issues it encounters to an error writer.
-func lint(vm *jsonnet.VM, node nodeWithLocation, errWriter *ErrorWriter) {
+func lint(vm *jsonnet.VM, nodes []nodeWithLocation, errWriter *ErrorWriter) {
 	roots := make(map[string]ast.Node)
-	roots[node.path] = node.node
-	getImports(vm, node, roots, errWriter)
+	for _, node := range nodes {
+		roots[node.path] = node.node
+	}
+	for _, node := range nodes {
+		getImports(vm, node, roots, errWriter)
+	}
 
 	variablesInFile := make(map[string]common.VariableInfo)
 
@@ -55,35 +65,38 @@ func lint(vm *jsonnet.VM, node nodeWithLocation, errWriter *ErrorWriter) {
 		return variables.FindVariables(node.node, variables.Environment{"std": &std})
 	}
 
-	variableInfo := findVariables(node)
 	for importedPath, rootNode := range roots {
 		variablesInFile[importedPath] = *findVariables(nodeWithLocation{rootNode, importedPath})
 	}
 
-	for _, v := range variableInfo.Variables {
-		if len(v.Occurences) == 0 && v.VariableKind == common.VarRegular && v.Name != "$" {
-			errWriter.writeError(vm, errors.MakeStaticError("Unused variable: "+string(v.Name), v.LocRange))
-		}
-	}
-	ec := common.ErrCollector{}
-
 	vars := make(map[string]map[ast.Node]*common.Variable)
 	for importedPath, info := range variablesInFile {
 		vars[importedPath] = info.VarAt
 	}
 
-	types.Check(node.node, roots, vars, func(currentPath, importedPath string) ast.Node {
-		node, _, err := vm.ImportAST(currentPath, importedPath)
-		if err != nil {
-			return nil
+	for _, node := range nodes {
+		variableInfo := findVariables(node)
+
+		for _, v := range variableInfo.Variables {
+			if len(v.Occurences) == 0 && v.VariableKind == common.VarRegular && v.Name != "$" {
+				errWriter.writeError(vm, errors.MakeStaticError("Unused variable: "+string(v.Name), v.LocRange))
+			}
 		}
-		return node
-	}, &ec)
+		ec := common.ErrCollector{}
+
+		types.Check(node.node, roots, vars, func(currentPath, importedPath string) ast.Node {
+			node, _, err := vm.ImportAST(currentPath, importedPath)
+			if err != nil {
+				return nil
+			}
+			return node
+		}, &ec)
 
-	traversal.Traverse(node.node, &ec)
+		traversal.Traverse(node.node, &ec)
 
-	for _, err := range ec.Errs {
-		errWriter.writeError(vm, err)
+		for _, err := range ec.Errs {
+			errWriter.writeError(vm, err)
+		}
 	}
 }
 
@@ -118,18 +131,24 @@ func getImports(vm *jsonnet.VM, node nodeWithLocation, roots map[string]ast.Node
 	}
 }
 
-// LintSnippet checks for problems in a single code snippet.
-func LintSnippet(vm *jsonnet.VM, output io.Writer, filename, code string) bool {
+// LintSnippet checks for problems in code snippet(s).
+func LintSnippet(vm *jsonnet.VM, output io.Writer, snippets []Snippet) bool {
 	errWriter := ErrorWriter{
 		Writer:      output,
 		ErrorsFound: false,
 	}
 
-	node, err := jsonnet.SnippetToAST(filename, code)
-	if err != nil {
-		errWriter.writeError(vm, err.(errors.StaticError)) // ugly but true
-		return true
+	var nodes []nodeWithLocation
+	for _, snippet := range snippets {
+		node, err := jsonnet.SnippetToAST(snippet.FileName, snippet.Code)
+
+		if err != nil {
+			errWriter.writeError(vm, err.(errors.StaticError)) // ugly but true
+		} else {
+			nodes = append(nodes, nodeWithLocation{node, snippet.FileName})
+		}
 	}
-	lint(vm, nodeWithLocation{node, filename}, &errWriter)
+
+	lint(vm, nodes, &errWriter)
 	return errWriter.ErrorsFound
 }
diff --git a/linter/linter_test.go b/linter/linter_test.go
index 953717948..8002e5d57 100644
--- a/linter/linter_test.go
+++ b/linter/linter_test.go
@@ -40,7 +40,7 @@ func runTest(t *testing.T, test *linterTest, changedGoldensList *ChangedGoldensL
 
 	var outBuilder strings.Builder
 
-	errorsFound := LintSnippet(vm, &outBuilder, test.name, string(input))
+	errorsFound := LintSnippet(vm, &outBuilder, []Snippet{Snippet{FileName: test.name, Code: string(input)}})
 
 	outData := outBuilder.String()
 
@@ -72,6 +72,40 @@ func runTest(t *testing.T, test *linterTest, changedGoldensList *ChangedGoldensL
 	}
 }
 
+func runTests(t *testing.T, tests []*linterTest) {
+	read := func(file string) []byte {
+		bytz, err := ioutil.ReadFile(file)
+		if err != nil {
+			t.Fatalf("reading file: %s: %v", file, err)
+		}
+		return bytz
+	}
+
+	vm := jsonnet.MakeVM()
+
+	var snippets []Snippet
+
+	for _, test := range tests {
+		input := read(test.input)
+
+		snippets = append(snippets, Snippet{FileName: test.name, Code: string(input)})
+	}
+
+	var outBuilder strings.Builder
+
+	errorsFound := LintSnippet(vm, &outBuilder, snippets)
+
+	outData := outBuilder.String()
+
+	if outData == "" && errorsFound {
+		t.Error(fmt.Errorf("return value indicates problems present, but no output was produced"))
+	}
+
+	if outData != "" && !errorsFound {
+		t.Error(fmt.Errorf("return value indicates no problems, but output is not empty:\n%v", outData))
+	}
+}
+
 func TestLinter(t *testing.T) {
 	flag.Parse()
 
@@ -122,4 +156,8 @@ func TestLinter(t *testing.T) {
 			t.Fail()
 		})
 	}
+
+	t.Run("passing multiple input files", func(t *testing.T) {
+		runTests(t, tests)
+	})
 }