Add leaves option to show modules that do not have dependencies

README.md

@@ -151,6 +151,18 @@ madge('path/to/app.js').then((res) => {
 });
 ```
 
+#### .leaves()
+
+> Return an `Array` of all modules that have no dependencies.
+
+```javascript
+const madge = require('madge');
+
+madge('path/to/app.js').then((res) => {
+ console.log(res.leaves());
+});
+```
+
 #### .dot()
 
 > Returns a `Promise` resolved with a DOT representation of the module dependency graph.
@@ -304,6 +316,10 @@ $ madge --depends wheels.js path/src/app.js
 $ madge --orphans path/src/
 ```
 
+```sh
+$ madge --leaves path/src/
+```
+
 > Excluding modules
 
 ```sh

bin/cli.js

@@ -22,6 +22,7 @@ program
  .option('-i, --image <file>', 'write graph to file as an image')
  .option('-l, --layout <name>', 'layout engine to use for graph (dot/neato/fdp/sfdp/twopi/circo)')
  .option('--orphans', 'show modules that no one is depending on')
+ .option('--leaves', 'show modules that have no dependencies')
  .option('--dot', 'show graph using the DOT language')
  .option('--extensions <list>', 'comma separated string of valid file extensions')
  .option('--require-config <file>', 'path to RequireJS config')
@@ -172,56 +173,9 @@ new Promise((resolve, reject) => {
  output.getResultSummary(res, startTime);
  }
 
- if (program.summary) {
- output.summary(res.obj(), {
- json: program.json
- });
-
- return res;
- }
-
- if (program.depends) {
- output.modules(res.depends(program.depends), {
- json: program.json
- });
-
- return res;
- }
-
- if (program.orphans) {
- output.modules(res.orphans(), {
- json: program.json
- });
-
- return res;
- }
-
- if (program.circular) {
- const circular = res.circular();
-
- output.circular(spinner, res, circular, {
- json: program.json
- });
-
- if (circular.length) {
- exitCode = 1;
- }
-
- return res;
- }
-
- if (program.image) {
- return res.image(program.image).then((imagePath) => {
- spinner.succeed(`${chalk.bold('Image created at')} ${chalk.cyan.bold(imagePath)}`);
- return res;
- });
- }
-
- if (program.dot) {
- return res.dot().then((output) => {
- process.stdout.write(output);
- return res;
- });
+ const result = createOutputFromOptions(program, res);
+ if (result !== undefined) {
+ return result;
  }
 
  output.list(res.obj(), {
@@ -246,3 +200,65 @@ new Promise((resolve, reject) => {
  console.log('\n%s %s\n', chalk.red('✖'), err.stack);
  process.exit(1);
  });
+
+function createOutputFromOptions(program, res) {
+ if (program.summary) {
+ output.summary(res.obj(), {
+ json: program.json
+ });
+
+ return res;
+ }
+
+ if (program.depends) {
+ output.modules(res.depends(program.depends), {
+ json: program.json
+ });
+
+ return res;
+ }
+
+ if (program.orphans) {
+ output.modules(res.orphans(), {
+ json: program.json
+ });
+
+ return res;
+ }
+
+ if (program.leaves) {
+ output.modules(res.leaves(), {
+ json: program.json
+ });
+
+ return res;
+ }
+
+ if (program.circular) {
+ const circular = res.circular();
+
+ output.circular(spinner, res, circular, {
+ json: program.json
+ });
+
+ if (circular.length) {
+ exitCode = 1;
+ }
+
+ return res;
+ }
+
+ if (program.image) {
+ return res.image(program.image).then((imagePath) => {
+ spinner.succeed(`${chalk.bold('Image created at')} ${chalk.cyan.bold(imagePath)}`);
+ return res;
+ });
+ }
+
+ if (program.dot) {
+ return res.dot().then((output) => {
+ process.stdout.write(output);
+ return res;
+ });
+ }
+}

lib/api.js

@@ -129,6 +129,16 @@ class Madge {
  .filter((dep) => !map[dep]);
  }
 
+ /**
+ * Return a list of modules that have no dependencies.
+ * @api public
+ * @return {Array}
+ */
+ leaves() {
+ const tree = this.obj();
+ return Object.keys(tree).filter((key) => !tree[key].length);
+ }
+
  /**
  * Return the module dependency graph as DOT output.
  * @api public

test/api.js

@@ -235,6 +235,15 @@ describe('API', () => {
  });
  });
 
+ describe('leaves()', () => {
+ it('returns modules that have no dependencies', (done) => {
+ madge(__dirname + '/cjs/normal').then((res) => {
+ res.leaves().should.eql(['d.js']);
+ done();
+ }).catch(done);
+ });
+ });
+
  describe('svg()', () => {
  it('returns a promise resolved with XML SVG output in a Buffer', (done) => {
  madge(__dirname + '/cjs/b.js')