formatting multiple hcl files (#13362)

* formatting multiple hcl files

* recursive formating

* test case fixing

* test case fix

* removed not required code

* existing test code fix

* go formatting

* more test cases for new cases

* doc changes

* added additional check on error message in negative test case

command/cli.go

@@ -66,6 +66,7 @@ type MetaArgs struct {
 	// TODO(azr): in the future, I want to allow passing multiple path to
 	// merge HCL confs together; but this will probably need an RFC first.
 	Path         string
+	Paths        []string
 	Only, Except []string
 	Vars         map[string]string
 	VarFiles     []string

command/fmt.go

@@ -36,12 +36,12 @@ func (c *FormatCommand) ParseArgs(args []string) (*FormatArgs, int) {
 	}
 
 	args = flags.Args()
-	if len(args) != 1 {
+	if len(args) == 0 {
 		flags.Usage()
 		return &cfg, 1
 	}
 
-	cfg.Path = args[0]
+	cfg.Paths = args
 	return &cfg, 0
 }
 
@@ -57,7 +57,7 @@ func (c *FormatCommand) RunContext(ctx context.Context, cla *FormatArgs) int {
 		Recursive: cla.Recursive,
 	}
 
-	bytesModified, diags := formatter.Format(cla.Path)
+	bytesModified, diags := formatter.Format(cla.Paths)
 	ret := writeDiags(c.Ui, nil, diags)
 	if ret != 0 {
 		return ret

hcl2template/formatter.go

@@ -55,52 +55,53 @@ func (f *HCL2Formatter) formatFile(path string, diags hcl.Diagnostics, bytesModi
 // If any error is encountered, zero bytes will be returned.
 //
 // Path can be a directory or a file.
-func (f *HCL2Formatter) Format(path string) (int, hcl.Diagnostics) {
+func (f *HCL2Formatter) Format(paths []string) (int, hcl.Diagnostics) {
 	var diags hcl.Diagnostics
 	var bytesModified int
 
-	if path == "" {
-		diags = append(diags, &hcl.Diagnostic{
-			Severity: hcl.DiagError,
-			Summary:  "path is empty, cannot format",
-			Detail:   "path is empty, cannot format",
-		})
-		return bytesModified, diags
-	}
-
 	if f.parser == nil {
 		f.parser = hclparse.NewParser()
 	}
 
-	if s, err := os.Stat(path); err != nil || !s.IsDir() {
-		return f.formatFile(path, diags, bytesModified)
-	}
+	for _, path := range paths {
+		s, err := os.Stat(path)
 
-	fileInfos, err := os.ReadDir(path)
-	if err != nil {
-		diag := &hcl.Diagnostic{
-			Severity: hcl.DiagError,
-			Summary:  "Cannot read hcl directory",
-			Detail:   err.Error(),
-		}
-		diags = append(diags, diag)
-		return bytesModified, diags
-	}
-
-	for _, fileInfo := range fileInfos {
-		filename := filepath.Join(path, fileInfo.Name())
-		if fileInfo.IsDir() {
-			if f.Recursive {
-				var tempDiags hcl.Diagnostics
-				var tempBytesModified int
-				tempBytesModified, tempDiags = f.Format(filename)
-				bytesModified += tempBytesModified
-				diags = diags.Extend(tempDiags)
+		if err != nil || !s.IsDir() {
+			bytesModified, diags = f.formatFile(path, diags, bytesModified)
+		} else {
+			fileInfos, err := os.ReadDir(path)
+			if err != nil {
+				diag := &hcl.Diagnostic{
+					Severity: hcl.DiagError,
+					Summary:  "Cannot read hcl directory",
+					Detail:   err.Error(),
+				}
+				diags = append(diags, diag)
+				return bytesModified, diags
+			}
+
+			for _, fileInfo := range fileInfos {
+				name := fileInfo.Name()
+				if f.shouldIgnoreFile(name) {
+					continue
+				}
+				filename := filepath.Join(path, name)
+				if fileInfo.IsDir() {
+					if f.Recursive {
+						var tempDiags hcl.Diagnostics
+						var tempBytesModified int
+						var newPaths []string
+						newPaths = append(newPaths, filename)
+						tempBytesModified, tempDiags = f.Format(newPaths)
+						bytesModified += tempBytesModified
+						diags = diags.Extend(tempDiags)
+					}
+					continue
+				}
+				if isHcl2FileOrVarFile(filename) {
+					bytesModified, diags = f.formatFile(filename, diags, bytesModified)
+				}
 			}
-			continue
-		}
-		if isHcl2FileOrVarFile(filename) {
-			bytesModified, diags = f.formatFile(filename, diags, bytesModified)
 		}
 	}
 
@@ -116,6 +117,10 @@ func (f *HCL2Formatter) processFile(filename string) ([]byte, error) {
 		f.Output = os.Stdout
 	}
 
+	if !(filename == "-") && !isHcl2FileOrVarFile(filename) {
+		return nil, fmt.Errorf("file %s is not a HCL file", filename)
+	}
+
 	var in io.Reader
 	var err error
 
@@ -175,6 +180,14 @@ func (f *HCL2Formatter) processFile(filename string) ([]byte, error) {
 	return outSrc, nil
 }
 
+// shouldIgnoreFile returns true if the given filename (which must not have a
+// directory path ahead of it) should be ignored as e.g. an editor swap file.
+func (f *HCL2Formatter) shouldIgnoreFile(name string) bool {
+	return strings.HasPrefix(name, ".") || // Unix-like hidden files
+		strings.HasSuffix(name, "~") || // vim
+		strings.HasPrefix(name, "#") && strings.HasSuffix(name, "#") // emacs
+}
+
 // bytesDiff returns the unified diff of b1 and b2
 // Shamelessly copied from Terraform's fmt command.
 func bytesDiff(b1, b2 []byte, path string) (data []byte, err error) {

hcl2template/formatter_test.go

@@ -16,13 +16,15 @@ import (
 func TestHCL2Formatter_Format(t *testing.T) {
 	tt := []struct {
 		Name           string
-		Path           string
+		Paths          []string
 		FormatExpected bool
 	}{
-		{Name: "Unformatted file", Path: "testdata/format/unformatted.pkr.hcl", FormatExpected: true},
-		{Name: "Unformatted vars file", Path: "testdata/format/unformatted.pkrvars.hcl", FormatExpected: true},
-		{Name: "Formatted file", Path: "testdata/format/formatted.pkr.hcl"},
-		{Name: "Directory", Path: "testdata/format", FormatExpected: true},
+		{Name: "Unformatted file", Paths: []string{"testdata/format/unformatted.pkr.hcl"}, FormatExpected: true},
+		{Name: "Unformatted vars file", Paths: []string{"testdata/format/unformatted.pkrvars.hcl"}, FormatExpected: true},
+		{Name: "Formatted file", Paths: []string{"testdata/format/formatted.pkr.hcl"}},
+		{Name: "Directory", Paths: []string{"testdata/format"}, FormatExpected: true},
+		{Name: "No file", Paths: []string{}, FormatExpected: false},
+		{Name: "Multi File", Paths: []string{"testdata/format/unformatted.pkr.hcl", "testdata/format/unformatted.pkrvars.hcl"}, FormatExpected: true},
 	}
 
 	for _, tc := range tt {
@@ -30,12 +32,12 @@ func TestHCL2Formatter_Format(t *testing.T) {
 		var buf bytes.Buffer
 		f := NewHCL2Formatter()
 		f.Output = &buf
-		_, diags := f.Format(tc.Path)
+		_, diags := f.Format(tc.Paths)
 		if diags.HasErrors() {
 			t.Fatalf("the call to Format failed unexpectedly %s", diags.Error())
 		}
 		if buf.String() != "" && tc.FormatExpected == false {
-			t.Errorf("Format(%q) should contain the name of the formatted file(s), but got %q", tc.Path, buf.String())
+			t.Errorf("Format(%q) should contain the name of the formatted file(s), but got %q", tc.Paths, buf.String())
 		}
 	}
 }
@@ -61,7 +63,9 @@ func TestHCL2Formatter_Format_Write(t *testing.T) {
 	_, _ = tf.Write(unformattedData)
 	tf.Close()
 
-	_, diags := f.Format(tf.Name())
+	var paths []string
+	paths = append(paths, tf.Name())
+	_, diags := f.Format(paths)
 	if diags.HasErrors() {
 		t.Fatalf("the call to Format failed unexpectedly %s", diags.Error())
 	}
@@ -94,7 +98,9 @@ func TestHCL2Formatter_Format_ShowDiff(t *testing.T) {
 		ShowDiff: true,
 	}
 
-	_, diags := f.Format("testdata/format/unformatted.pkr.hcl")
+	var paths []string
+	paths = append(paths, "testdata/format/unformatted.pkr.hcl")
+	_, diags := f.Format(paths)
 	if diags.HasErrors() {
 		t.Fatalf("the call to Format failed unexpectedly %s", diags.Error())
 	}
@@ -109,3 +115,28 @@ func TestHCL2Formatter_Format_ShowDiff(t *testing.T) {
 	}
 
 }
+
+func TestHCL2Formatter_FormatNegativeCases(t *testing.T) {
+	tt := []struct {
+		Name        string
+		Paths       []string
+		errExpected bool
+	}{
+		{Name: "Unformatted file", Paths: []string{"testdata/format/test.json"}, errExpected: true},
+	}
+
+	for _, tc := range tt {
+		tc := tc
+		var buf bytes.Buffer
+		f := NewHCL2Formatter()
+		f.Output = &buf
+		_, diags := f.Format(tc.Paths)
+		if tc.errExpected && !diags.HasErrors() {
+			t.Fatalf("Expected error but got none")
+		}
+
+		if diags[0].Detail != "file testdata/format/test.json is not a HCL file" {
+			t.Fatalf("Expected error messge did not received")
+		}
+	}
+}

hcl2template/testdata/format/test.json

@@ -0,0 +1,19 @@
+{
+  "builders": [
+    {
+      "type": "amazon-ebs",
+      "access_key": "YOUR_AWS_ACCESS_KEY",
+      "secret_key": "YOUR_AWS_SECRET_KEY",
+      "region": "us-east-1"
+    }
+  ],
+  "provisioners": [
+    {
+      "type": "shell",
+      "inline": [
+        "sudo apt-get update",
+        "sudo apt-get install -y nginx"
+      ]
+    }
+  ]
+}

website/content/docs/commands/fmt.mdx

@@ -32,6 +32,15 @@ my-template.pkr.hcl
 
 ```
 
+Format multiple configuration files, writing the changes back to respective original files.
+
+```shell-session
+$ packer fmt my-template.pkr.hcl my-varfile.pkrvars.hcl
+my-template.pkr.hcl
+my-varfile.pkrvars.hcl
+
+```
+
 Format a configuration file, reading from stdin and writing to stdout.
 
 ```shell-session