Remove 'async' dependency, used only in errorCheck.ts, modernize file (#50667)

Author: jakebailey

package-lock.json

@@ -40,7 +40,6 @@
     ],
     "devDependencies": {
         "@octokit/rest": "latest",
-        "@types/async": "latest",
         "@types/chai": "latest",
         "@types/fs-extra": "^9.0.13",
         "@types/glob": "latest",
@@ -62,7 +61,6 @@
         "@typescript-eslint/eslint-plugin": "^5.33.1",
         "@typescript-eslint/parser": "^5.33.1",
         "@typescript-eslint/utils": "^5.33.1",
-        "async": "latest",
         "azure-devops-node-api": "^11.2.0",
         "chai": "latest",
         "chalk": "^4.1.2",

package.json

@@ -1,12 +1,12 @@
 import * as fs from "fs";
-import * as async from "async";
-import * as glob from "glob";
+import * as fsPromises from "fs/promises";
+import * as _glob from "glob";
+import * as util from "util";
 
-fs.readFile("src/compiler/diagnosticMessages.json", "utf-8", (err, data) => {
-    if (err) {
-        throw err;
-    }
+const glob = util.promisify(_glob);
 
+async function checkErrorBaselines() {
+    const data = await fsPromises.readFile("src/compiler/diagnosticMessages.json", "utf-8");
     const messages = JSON.parse(data);
     const keys = Object.keys(messages);
     console.log("Loaded " + keys.length + " errors");
@@ -18,39 +18,35 @@ fs.readFile("src/compiler/diagnosticMessages.json", "utf-8", (err, data) => {
     const errRegex = /\(\d+,\d+\): error TS([^:]+):/g;
     const baseDir = "tests/baselines/reference/";
 
-    fs.readdir(baseDir, (err, files) => {
-        files = files.filter(f => f.indexOf(".errors.txt") > 0);
-        const tasks: ((callback: () => void) => void)[] = [];
-        files.forEach(f => tasks.push(done => {
-            fs.readFile(baseDir + f, "utf-8", (err, baseline) => {
-                if (err) throw err;
-
-                let g: RegExpExecArray | null;
-                while (g = errRegex.exec(baseline)) {
-                    const errCode = +g[1];
-                    const msg = keys.filter(k => messages[k].code === errCode)[0];
-                    messages[msg].seen = true;
-                }
-
-                done();
-            });
-        }));
-
-        async.parallelLimit(tasks, 25, done => {
-            console.log("== List of errors not present in baselines ==");
-            let count = 0;
-            for (const k of keys) {
-                if (messages[k].seen !== true) {
-                    console.log(k);
-                    count++;
-                }
+    const files = (await fsPromises.readdir(baseDir)).filter(f => f.endsWith(".errors.txt"));
+
+    files.forEach(f => {
+        fs.readFile(baseDir + f, "utf-8", (err, baseline) => {
+            if (err) throw err;
+
+            let g: RegExpExecArray | null;
+            while (g = errRegex.exec(baseline)) {
+                const errCode = +g[1];
+                const msg = keys.filter(k => messages[k].code === errCode)[0];
+                messages[msg].seen = true;
             }
-            console.log(count + " of " + keys.length + " errors are not in baselines");
         });
     });
-});
 
-fs.readFile("src/compiler/diagnosticInformationMap.generated.ts", "utf-8", (err, data) => {
+    console.log("== List of errors not present in baselines ==");
+    let count = 0;
+    for (const k of keys) {
+        if (messages[k].seen !== true) {
+            console.log(k);
+            count++;
+        }
+    }
+    console.log(count + " of " + keys.length + " errors are not in baselines");
+}
+
+async function checkSourceFiles() {
+    const data = await fsPromises.readFile("src/compiler/diagnosticInformationMap.generated.ts", "utf-8");
+
     const errorRegexp = /\s(\w+): \{ code/g;
     const errorNames: string[] = [];
     let errMatch: RegExpExecArray | null;
@@ -59,27 +55,33 @@ fs.readFile("src/compiler/diagnosticInformationMap.generated.ts", "utf-8", (err,
     }
 
     let allSrc = "";
-    glob("./src/**/*.ts", {}, (err, files) => {
-        console.log("Reading " + files.length + " source files");
-        for (const file of files) {
-            if (file.indexOf("diagnosticInformationMap.generated.ts") > 0) {
-                continue;
-            }
-
-            const src = fs.readFileSync(file, "utf-8");
-            allSrc = allSrc + src;
+    const files = await glob("./src/**/*.ts");
+    console.log("Reading " + files.length + " source files");
+    for (const file of files) {
+        if (file.indexOf("diagnosticInformationMap.generated.ts") > 0) {
+            continue;
         }
 
-        console.log("Consumed " + allSrc.length + " characters of source");
+        const src = fs.readFileSync(file, "utf-8");
+        allSrc = allSrc + src;
+    }
+
+    console.log("Consumed " + allSrc.length + " characters of source");
 
-        let count = 0;
-        console.log("== List of errors not used in source ==");
-        for (const errName of errorNames) {
-            if (allSrc.indexOf(errName) < 0) {
-                console.log(errName);
-                count++;
-            }
+    let count = 0;
+    console.log("== List of errors not used in source ==");
+    for (const errName of errorNames) {
+        if (allSrc.indexOf(errName) < 0) {
+            console.log(errName);
+            count++;
         }
-        console.log(count + " of " + errorNames.length + " errors are not used in source");
-    });
-});
+    }
+    console.log(count + " of " + errorNames.length + " errors are not used in source");
+}
+
+async function main() {
+    await checkErrorBaselines();
+    await checkSourceFiles();
+}
+
+main();