Fix coverage

.c8rc

@@ -4,7 +4,6 @@
     "lcov"
   ],
   "exclude": [
-    "**/test/*.test.js",
-    "**/node_modules/**"
+    "test/*.test.js"
   ]
 }

.github/workflows/node.js.yml

@@ -12,7 +12,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [18.x, 20.x, 21.x]
+        node-version: [18.x, 20.x, 21.x, 22.x]
         platform: [ubuntu-latest]
 
     runs-on: ${{ matrix.platform }}
@@ -37,7 +37,7 @@ jobs:
       - name: Test ${{ matrix.node-version }} ${{ matrix.platform }}
         run: npm run test
       - name: Upload coverage reports to Codecov
-        uses: codecov/codecov-action@v4.0.1
+        uses: codecov/codecov-action@v4
         with:
           token: ${{ secrets.CODECOV_TOKEN }}
           slug: peggyjs/coverage

lib/index.d.ts

@@ -1,12 +1,26 @@
+/**
+ * @typedef {object} TestPeggyOptions
+ * @prop {boolean} [noDelete] Do not delete the generated file.
+ * @prop {boolean} [noMap] Do not add a sourcemap to the generated file.
+ *   Defaults to true if peggy$debugger is set on any start, otherwise false.
+ * @prop {boolean} [noGenerate] Do not generate a file, only run tests on the
+ *   original.
+ */
 /**
  * Test the basic functionality of a Peggy grammar, to make coverage easier.
  *
  * @template T
  * @param {URL | string} grammarUrl The file name for the compiled grammar.
  * @param {PeggyTestOptions<T>[]} starts List of tests.  Ensure you have at
  *   least one validInput and at least one invalidInput.
+ * @param {TestPeggyOptions} [opts] Options for processing.
+ * @returns {Promise<TestCounts>}
  */
-export function testPeggy<T>(grammarUrl: URL | string, starts: PeggyTestOptions<T>[]): Promise<void>;
+export function testPeggy<T>(grammarUrl: URL | string, starts: PeggyTestOptions<T>[], opts?: TestPeggyOptions | undefined): Promise<TestCounts>;
+export type TestCounts = {
+    valid: number;
+    invalid: number;
+};
 export type ExtraParserOptions = {
     /**
      * In the augmented code only, use this
@@ -57,3 +71,19 @@ export type Parser = import('peggy').Parser & {
     StartRules: string[];
 };
 export type Location = import('peggy').Location;
+export type TestPeggyOptions = {
+    /**
+     * Do not delete the generated file.
+     */
+    noDelete?: boolean | undefined;
+    /**
+     * Do not add a sourcemap to the generated file.
+     * Defaults to true if peggy$debugger is set on any start, otherwise false.
+     */
+    noMap?: boolean | undefined;
+    /**
+     * Do not generate a file, only run tests on the
+     * original.
+     */
+    noGenerate?: boolean | undefined;
+};

lib/index.js

@@ -12,6 +12,12 @@ import path from "node:path";
 
 const INVALID = "\uffff";
 
+/**
+ * @typedef {object} TestCounts
+ * @prop {number} valid
+ * @prop {number} invalid
+ */
+
 /**
  * @typedef {object} ExtraParserOptions
  * @prop {string} [peg$startRuleFunction] In the augmented code only, use this
@@ -51,8 +57,9 @@ const INVALID = "\uffff";
  * @param {Parser} grammar
  * @param {PeggyTestOptions<T>[]} starts
  * @param {boolean} modified
+ * @param {TestCounts} counts
  */
-function checkParserStarts(grammar, starts, modified) {
+function checkParserStarts(grammar, starts, modified, counts) {
   for (const start of starts) {
     const startRule = start.startRule || undefined;  // NOT `??`
     const peg$maxFailPos = start.peg$maxFailPos ?? 0;
@@ -113,6 +120,7 @@ function checkParserStarts(grammar, starts, modified) {
           ...options,
         }));
       }
+      counts.valid++;
     }
 
     if (typeof start.invalidInput === "string") {
@@ -156,19 +164,40 @@ function checkParserStarts(grammar, starts, modified) {
         }]);
         equal(typeof fmt, "string");
       }
+      counts.invalid++;
     }
   }
 }
 
+/**
+ * @typedef {object} TestPeggyOptions
+ * @prop {boolean} [noDelete] Do not delete the generated file.
+ * @prop {boolean} [noMap] Do not add a sourcemap to the generated file.
+ *   Defaults to true if peggy$debugger is set on any start, otherwise false.
+ * @prop {boolean} [noGenerate] Do not generate a file, only run tests on the
+ *   original.
+ */
+
 /**
  * Test the basic functionality of a Peggy grammar, to make coverage easier.
  *
  * @template T
  * @param {URL | string} grammarUrl The file name for the compiled grammar.
  * @param {PeggyTestOptions<T>[]} starts List of tests.  Ensure you have at
  *   least one validInput and at least one invalidInput.
+ * @param {TestPeggyOptions} [opts] Options for processing.
+ * @returns {Promise<TestCounts>}
  */
-export async function testPeggy(grammarUrl, starts) {
+export async function testPeggy(grammarUrl, starts, opts) {
+  /** @type {TestCounts} */
+  const counts = {
+    valid: 0,
+    invalid: 0,
+  };
+
+  if (!(typeof grammarUrl === "string") && !(grammarUrl instanceof URL)) {
+    throw new TypeError("Invalid grammarUrl");
+  }
   let grammarPath = String(grammarUrl);
   if (grammarPath.startsWith("file:")) {
     grammarPath = fileURLToPath(grammarPath);
@@ -198,20 +227,21 @@ export async function testPeggy(grammarUrl, starts) {
       startRule,
     }));
   }
-  checkParserStarts(grammar, starts, false);
+  checkParserStarts(grammar, starts, false, counts);
 
   const grammarJs = await fs.readFile(grammarPath, "utf8");
   ok(grammarJs);
   equal(typeof grammarJs, "string");
 
-  // Approach: generate a new file next to the existing grammar file, with
-  // test code injected just before the parser runs.  Source map information
-  // embedded in the new file will make coverage show up on the original file.
-  const src = new SourceNode();
-  let lineNum = 1;
-  for (const line of grammarJs.split(/(?<=\n)/)) {
-    if (/^\s*peg\$result = peg\$startRuleFunction\(\);/.test(line)) {
-      src.add(`\
+  if (!opts?.noGenerate) {
+    // Approach: generate a new file next to the existing grammar file, with
+    // test code injected just before the parser runs.  Source map information
+    // embedded in the new file will make coverage show up on the original file.
+    const src = new SourceNode();
+    let lineNum = 1;
+    for (const line of grammarJs.split(/(?<=\n)/)) {
+      if (/^\s*peg\$result = peg\$startRuleFunction\(\);/.test(line)) {
+        src.add(`\
   (() => {
     if (options.peg$debugger) {
       debugger;
@@ -293,37 +323,45 @@ export async function testPeggy(grammarUrl, starts) {
   })();
 
 `);
+      }
+      src.add(new SourceNode(lineNum++, 0, grammarPath, line));
     }
-    src.add(new SourceNode(lineNum++, 0, grammarPath, line));
-  }
 
-  const withMap = src.toStringWithSourceMap();
-  const map = Buffer.from(withMap.map.toString()).toString("base64");
-  let code = withMap.code;
-  if (starts.every(s => !s.options?.peg$debugger)) {
-    code += `
-//# sourceMappingURL=data:application/json;charset=utf-8;base64,${map}
-`;
-  }
+    const withMap = src.toStringWithSourceMap();
+    const map = Buffer.from(withMap.map.toString()).toString("base64");
+    let code = withMap.code;
+    const sm = (opts && Object.prototype.hasOwnProperty.call(opts, "noMap"))
+      ? !opts.noMap
+      : starts.every(s => !s.options?.peg$debugger);
+    const start = "//# "; // c8: THIS file is not mapped.
+    if (sm) {
+      code += `
+  ${start}sourceMappingURL=data:application/json;charset=utf-8;base64,${map}
+  `;
+    }
 
-  // Can't use @peggyjs/from-mem since c8 can't see into those modules for
-  // coverage.  Maybe file a bug on c8? Given that, the modified file MUST be
-  // written to the same directory, with the same file name, so that `import`
-  // or `require` of relative paths or npm modules will work as expected.
-  const gp = path.parse(grammarPath);
-  // @ts-expect-error This TS error is bogus.
-  delete gp.base;
-  gp.name += `___TEST-${process.pid}`;
-  const modifiedPath = path.format(gp);
+    // Can't use @peggyjs/from-mem since c8 can't see into those modules for
+    // coverage.  Maybe file a bug on c8? Given that, the modified file MUST be
+    // written to the same directory, with the same file name, so that `import`
+    // or `require` of relative paths or npm modules will work as expected.
+    const gp = path.parse(grammarPath);
+    // @ts-expect-error This TS error is bogus.
+    delete gp.base;
+    gp.name += `___TEST-${process.pid}`;
+    const modifiedPath = path.format(gp);
 
-  await fs.writeFile(modifiedPath, code);
-  try {
-    const agrammar = /** @type {Parser} */ (
-      await import(modifiedPath)
-    );
-    ok(agrammar);
-    checkParserStarts(agrammar, starts, true);
-  } finally {
-    await fs.rm(modifiedPath);
+    await fs.writeFile(modifiedPath, code);
+    try {
+      const agrammar = /** @type {Parser} */ (
+        await import(modifiedPath)
+      );
+      ok(agrammar);
+      checkParserStarts(agrammar, starts, true, counts);
+    } finally {
+      if (!opts?.noDelete) {
+        await fs.rm(modifiedPath);
+      }
+    }
   }
+  return counts;
 }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@peggyjs/coverage",
-  "version": "1.0.0",
+  "version": "1.1.0",
   "decription": "Generate better code coverage for Peggy grammars",
   "main": "lib/index.js",
   "type": "module",
@@ -25,7 +25,7 @@
   "scripts": {
     "build": "peggy --format es test/minimal.peggy && tsc",
     "lint": "eslint .",
-    "test": "c8 node --test"
+    "test": "c8 node --test test/*.test.js"
   },
   "dependencies": {
     "peggy": "4.0.2",

test/index.test.js

@@ -1,8 +1,9 @@
+import { deepEqual, rejects } from "node:assert";
 import test from "node:test";
 import { testPeggy } from "../lib/index.js";
 
 test("test peggy coverage", async() => {
-  await testPeggy(new URL("minimal.js", import.meta.url), [
+  const counts = await testPeggy(new URL("minimal.js", import.meta.url), [
     {
       validInput: "foo",
       invalidInput: "",
@@ -31,5 +32,63 @@ test("test peggy coverage", async() => {
         peg$silentFails: -1,
       },
     },
+    {
+      validInput: "a",
+      validResult(r) {
+        return r;
+      },
+      peg$maxFailPos: 1,
+      options: {
+        peg$startRuleFunction: "peg$parseinit",
+      },
+    },
+    {
+      validInput: "aa",
+      validResult: ["a", "a"],
+      peg$maxFailPos: 2,
+      options: {
+        peg$startRuleFunction: "peg$parseinit",
+      },
+    },
   ]);
+  deepEqual(counts, {
+    valid: 10,
+    invalid: 8,
+  });
+});
+
+test("noGenerate", async() => {
+  const counts = await testPeggy(new URL("minimal.js", import.meta.url), [
+    {
+      validInput: "foo",
+      invalidInput: "",
+    },
+  ], {
+    noGenerate: true,
+  });
+
+  deepEqual(counts, {
+    valid: 1,
+    invalid: 1,
+  });
+});
+
+test("noMap", async() => {
+  const counts = await testPeggy(new URL("minimal.js", import.meta.url), [
+    {
+      validInput: "foo",
+      invalidInput: "",
+    },
+  ], {
+    noMap: true,
+  });
+
+  deepEqual(counts, {
+    valid: 2,
+    invalid: 2,
+  });
+});
+
+test("edges", async() => {
+  await rejects(() => testPeggy(), TypeError);
 });

test/minimal.js

@@ -408,15 +408,30 @@ function peg$parse(input, options) {
   }
 
   function peg$parseinit() {
-    var s0;
+    var s0, s1;
 
-    s0 = input.charAt(peg$currPos);
-    if (peg$r0.test(s0)) {
+    s0 = [];
+    s1 = input.charAt(peg$currPos);
+    if (peg$r0.test(s1)) {
       peg$currPos++;
     } else {
-      s0 = peg$FAILED;
+      s1 = peg$FAILED;
       if (peg$silentFails === 0) { peg$fail(peg$e2); }
     }
+    if (s1 !== peg$FAILED) {
+      while (s1 !== peg$FAILED) {
+        s0.push(s1);
+        s1 = input.charAt(peg$currPos);
+        if (peg$r0.test(s1)) {
+          peg$currPos++;
+        } else {
+          s1 = peg$FAILED;
+          if (peg$silentFails === 0) { peg$fail(peg$e2); }
+        }
+      }
+    } else {
+      s0 = peg$FAILED;
+    }
 
     return s0;
   }

test/minimal.peggy

@@ -3,7 +3,7 @@ foo
   = (ws / init)* @$("fo" .)
 
 init
-  = [a-b\x7f]
+  = [a-b\x7f]+
 
 ws "whitespace"
   =  [ \t\r\n]