feat: support local paths (#101)

For local packages, follow local package references.

Fixes: #96

src/checker.ts

@@ -229,9 +229,34 @@ export class LicenseChecker extends EventEmitter {
     }
   }
 
+  private async getPackageJson(
+    packageName: string,
+    versionSpec: string,
+    localDirectory: string | null
+  ): Promise<{}> {
+    // If this has a relative URL, and is a local package, find the package json from the
+    // indicated directory
+    if (versionSpec.startsWith('file:') && localDirectory) {
+      const relativePath = versionSpec.slice('file:'.length);
+      const packageJsonPath = path.join(
+        localDirectory,
+        relativePath,
+        'package.json'
+      );
+      this.emit('package.json', packageJsonPath);
+      const contents = await fsReadFile(packageJsonPath, 'utf8');
+      return JSON.parse(contents);
+    }
+    return packageJson(packageName, {
+      version: versionSpec,
+      fullMetadata: true,
+    });
+  }
+
   private async checkLicenses(
     packageName: string,
     versionSpec: string,
+    localDirectory: string | null,
     ...parents: string[]
   ): Promise<void> {
     const spec = `${packageName}@${versionSpec}`;
@@ -243,11 +268,17 @@ export class LicenseChecker extends EventEmitter {
     if (this.localPackages.has(`${packageName}@${version}`)) return;
 
     try {
-      const json = await packageJson(packageName, {
-        version: versionSpec,
-        fullMetadata: true,
-      });
-      await this.checkPackageJson(json, packageName, ...parents);
+      const json = await this.getPackageJson(
+        packageName,
+        versionSpec,
+        localDirectory
+      );
+      await this.checkPackageJson(
+        json,
+        packageName,
+        localDirectory,
+        ...parents
+      );
     } catch (err) {
       this.failedPackages.add(spec);
       this.emit('error', {
@@ -261,18 +292,20 @@ export class LicenseChecker extends EventEmitter {
 
   private async checkLicensesForDeps(
     deps: Dependencies | undefined,
+    localDirectory: string | null,
     ...parents: string[]
   ): Promise<void> {
     if (!deps) return;
     for (const pkg of Object.keys(deps)) {
       const depVersion = deps[pkg];
-      await this.checkLicenses(pkg, depVersion, ...parents);
+      await this.checkLicenses(pkg, depVersion, localDirectory, ...parents);
     }
   }
 
   private async checkPackageJson(
     json: {},
     packageName: string | null,
+    localDirectory: string | null,
     ...parents: string[]
   ): Promise<void> {
     const pj: PackageJson = ensurePackageJson(json);
@@ -305,24 +338,29 @@ export class LicenseChecker extends EventEmitter {
 
     await this.checkLicensesForDeps(
       pj.dependencies,
+      localDirectory,
       ...parents,
       packageAndVersion
     );
     if (this.opts.dev) {
       await this.checkLicensesForDeps(
         pj.devDependencies,
+        localDirectory,
         ...parents,
         packageAndVersion
       );
     }
   }
 
-  private async checkPackageJsonContent(content: string): Promise<void> {
+  private async checkPackageJsonContent(
+    content: string,
+    localDirectory: string | null
+  ): Promise<void> {
     // tslint:disable-next-line:no-any `JSON.parse()` returns any
     let json: any = null;
     try {
       json = JSON.parse(content);
-      await this.checkPackageJson(json, json.name);
+      await this.checkPackageJson(json, json.name, localDirectory);
     } catch (err) {
       const packageName = (json && json.name) || '(unknown package)';
       const versionSpec = (json && json.version) || '(unknown version)';
@@ -383,7 +421,7 @@ export class LicenseChecker extends EventEmitter {
     for (const pj of packageJsons) {
       this.emit('package.json', pj);
       const content = await fsReadFile(pj, 'utf8');
-      await this.checkPackageJsonContent(content);
+      await this.checkPackageJsonContent(content, path.dirname(pj));
     }
     this.emit('end');
   }
@@ -399,7 +437,7 @@ export class LicenseChecker extends EventEmitter {
     if (!pkgArgs.name || !pkgArgs.fetchSpec) {
       throw new Error(`Invalid package spec: ${pkg}`);
     }
-    await this.checkLicenses(pkgArgs.name, pkgArgs.fetchSpec);
+    await this.checkLicenses(pkgArgs.name, pkgArgs.fetchSpec, null);
     this.emit('end');
   }
 
@@ -430,7 +468,7 @@ export class LicenseChecker extends EventEmitter {
     }
     for (const pj of packageJsons) {
       this.emit('package.json', pj.filePath);
-      await this.checkPackageJsonContent(pj.content);
+      await this.checkPackageJsonContent(pj.content, null);
     }
     this.emit('end');
   }

test/checker-test.ts

@@ -386,3 +386,60 @@ test.serial('decline private package (local repo)', t => {
     }
   );
 });
+
+test.serial('support local paths', t => {
+  const primaryPackageJson = JSON.stringify({
+    name: 'hello',
+    version: '1.0.0',
+    license: 'Apache-2.0',
+    dependencies: {
+      foo: '^1.2.3',
+      linked: 'file:../linked',
+    },
+  });
+  const linkedPackageJson = JSON.stringify({
+    name: 'linked',
+    version: '1.0.0',
+    license: 'Apache-2.0',
+    dependencies: {
+      baz: '^7.0.0',
+    },
+  });
+  return withFixtures(
+    {
+      'path/to/primary': {
+        'package.json': primaryPackageJson,
+        'another-file': 'meh, world.',
+      },
+      'path/to/linked': {
+        'package.json': linkedPackageJson,
+        'another-file': 'i depend on a package with an evil license',
+      },
+    },
+    async () => {
+      requestedPackages = [];
+      const nonGreenPackages: string[] = [];
+      const packageJsonPaths: string[] = [];
+      const checker = new LicenseChecker();
+      checker
+        .on('non-green-license', arg => {
+          nonGreenPackages.push(`${arg.packageName}@${arg.version}`);
+        })
+        .on('package.json', filePath => {
+          packageJsonPaths.push(filePath);
+        });
+      await checker.checkLocalDirectory('path/to/primary');
+      console.log('requested packages: ', requestedPackages);
+      t.deepEqual(requestedPackages, [
+        'foo@^1.2.3',
+        'bar@^4.5.0',
+        'baz@^7.0.0',
+      ]);
+      t.deepEqual(nonGreenPackages, ['bar@4.5.6', 'baz@7.8.9']);
+      t.deepEqual(packageJsonPaths, [
+        'path/to/primary/package.json',
+        'path/to/linked/package.json',
+      ]);
+    }
+  );
+});