Merge pull request #105 from siefkenj/fixes1

Add ability to specify --dependency style deps

examples/bar.ts

@@ -0,0 +1,3 @@
+// This file exists as a dependency of minimal-with-dep.pegjs
+const foo = 'I AM THE CONST FOO';
+export default foo;

examples/minimal-with-dep.pegjs

@@ -0,0 +1,2 @@
+START
+  = "a" { return foo }

src/passes/generate-ts.ts

@@ -1,4 +1,5 @@
 import type { Config, ast } from 'peggy';
+import { escapedString } from '../libs/helpers';
 import { TypeExtractor } from '../libs/type-extractor';
 import { TsPegjsParserBuildOptions } from '../types';
 import { COMMON_TYPES_STR } from './constants';
@@ -59,6 +60,13 @@ export const generateParser: Config['passes']['generate'][number] = (
   // Set a new rootNode that we control
   ast.code = rootNode;
 
+  if (options.dependencies) {
+    const dependencyImports = Object.entries(options.dependencies).map(
+      ([varName, importPath]) => `import ${varName} from ${escapedString(importPath)};`
+    );
+    rootNode.prepend('\n' + dependencyImports.join('\n') + '\n');
+  }
+
   // Custom import statements should come near the top, if there are any
   if (options.tspegjs?.customHeader) {
     rootNode.prepend(options.tspegjs.customHeader + '\n\n');

src/types.ts

@@ -35,4 +35,5 @@ interface _ParserBuildOptions extends BuildOptionsBase {
 export type TsPegjsParserBuildOptions = _ParserBuildOptions & {
   tspegjs?: TsPegjsOptions;
   returnTypes?: Record<string, string>;
+  dependencies?: Record<string, string>;
 };

test/cli.test.ts

@@ -9,7 +9,6 @@ import peggy from 'peggy';
 
 // Local imports
 import packageJson from '../package.json';
-import tspegjs from '../src/tspegjs';
 
 const exec = promisify(execNode);
 
@@ -44,6 +43,38 @@ describe('CLI Tests', () => {
       throw new Error(stderr);
     }
   });
+  it(`Can specify dependency list`, async () => {
+    const GRAMMAR_FILE = path.join(ROOT_DIR, 'examples/minimal-with-dep.pegjs');
+    const outTsName = path.join(ROOT_DIR, 'output/minimal-with-dep.ts');
+    const barSource = path.join(ROOT_DIR, 'examples/bar.ts');
+    const barDest = path.join(ROOT_DIR, 'output/bar.ts');
+    // Copy the dependency to the output directory
+    await exec(`cp "${barSource}" "${barDest}"`);
+    {
+      // Create the parser
+      const { stdout, stderr } = await exec(
+        `npx peggy --plugin "${PLUGIN_PATH}" --dependency foo:./bar -o "${outTsName}" "${GRAMMAR_FILE}"`
+      );
+      if (stderr) {
+        throw new Error(stderr);
+      }
+    }
+    {
+      // Compile the parser
+      const { stdout, stderr } = await exec(
+        `tsc --target es6 --module commonjs --declaration "${outTsName}"`
+      );
+      if (stderr) {
+        throw new Error(stderr);
+      }
+    }
+    {
+      // Run the parser
+      const parserPath = path.join(ROOT_DIR, 'output/minimal-with-dep.js');
+      const parser = await import(parserPath);
+      expect(parser.parse('a')).toEqual('I AM THE CONST FOO');
+    }
+  });
 });
 
 /**