Add a script to check for dead code (#22793)

package.json

@@ -51,7 +51,8 @@
     "lint:types": "tsc --noEmit --jsx react && tsc --noEmit --project ./tsconfig.module_system.json",
     "lint:style": "stylelint \"res/css/**/*.scss\"",
     "test": "jest",
-    "coverage": "yarn test --coverage"
+    "coverage": "yarn test --coverage",
+    "analyse:unused-exports": "node ./scripts/analyse_unused_exports.js"
   },
   "dependencies": {
     "@matrix-org/olm": "https://gitlab.matrix.org/api/v4/projects/27/packages/npm/@matrix-org/olm/-/@matrix-org/olm-3.2.8.tgz",
@@ -155,6 +156,7 @@
     "stylelint-config-standard": "^20.0.0",
     "stylelint-scss": "^3.18.0",
     "terser-webpack-plugin": "^2.3.8",
+    "ts-prune": "^0.10.3",
     "typescript": "^4.5.3",
     "webpack": "^4.46.0",
     "webpack-cli": "^3.3.12",

scripts/analyse_unused_exports.js

@@ -0,0 +1,42 @@
+#!/usr/bin/env node
+'use strict';
+
+const fs = require("fs");
+const { exec } = require("node:child_process");
+
+const ignore = [];
+
+ignore.push(...Object.values(JSON.parse(fs.readFileSync(`${__dirname}/../components.json`))));
+ignore.push("/index.ts");
+
+const command = `yarn ts-prune --ignore "${ignore.join("|")}" | grep -v "(used in module)"`;
+
+exec(command, (error, stdout) => {
+    if (error) throw error;
+
+    let lines = stdout.split("\n");
+    // Remove the first line as that is the command that was being run and we
+    // log that only in case of an error
+    lines.splice(0, 1);
+    // Remove the last line as it is empty
+    lines.pop();
+
+    // ts-prune has bug where if the unused export is in a dependency, the path
+    // won't have an "/" character at the start, so we try to fix that for
+    // better UX
+    // TODO: This might break on Windows
+    lines = lines.reduce((newLines, line) => {
+        if (!line.startsWith("/")) newLines.push("/" + line);
+        else newLines.push(line);
+        return newLines;
+    }, []);
+
+    // If an unused export has been found, we error
+    if (lines.length > 0) {
+        console.log(`Command that was run: ${command}`);
+        console.log(lines.join("\n"));
+        throw Error("Unused exports found!");
+    }
+
+    console.log("Success - no unused exports found!");
+});

yarn.lock

@@ -1911,6 +1911,16 @@
   resolved "https://registry.yarnpkg.com/@tootallnate/once/-/once-1.1.2.tgz#ccb91445360179a04e7fe6aff78c00ffc1eeaf82"
   integrity sha512-RbzJvlNzmRq5c3O09UipeuXno4tA1FE6ikOjxZK0tuxVv3412l64l5t1W5pj4+rJq9vpkm/kwiR07aZXnsKPxw==
 
+"@ts-morph/common@~0.12.3":
+  version "0.12.3"
+  resolved "https://registry.yarnpkg.com/@ts-morph/common/-/common-0.12.3.tgz#a96e250217cd30e480ab22ec6a0ebbe65fd784ff"
+  integrity sha512-4tUmeLyXJnJWvTFOKtcNJ1yh0a3SsTLi2MUoyj8iUNznFRN1ZquaNe7Oukqrnki2FzZkm0J9adCNLDZxUzvj+w==
+  dependencies:
+    fast-glob "^3.2.7"
+    minimatch "^3.0.4"
+    mkdirp "^1.0.4"
+    path-browserify "^1.0.1"
+
 "@types/aria-query@^4.2.0":
   version "4.2.2"
   resolved "https://registry.yarnpkg.com/@types/aria-query/-/aria-query-4.2.2.tgz#ed4e0ad92306a704f9fb132a0cfcf77486dbe2bc"
@@ -3746,6 +3756,11 @@ coa@^2.0.2:
     chalk "^2.4.1"
     q "^1.1.2"
 
+code-block-writer@^11.0.0:
+  version "11.0.1"
+  resolved "https://registry.yarnpkg.com/code-block-writer/-/code-block-writer-11.0.1.tgz#53920acb587af3f7be57101c0248d98f372d73ac"
+  integrity sha512-0ch9DeCY8v/BWA9n1/Qu1ALG3lpesel4PYL2eNlGLgvGl+J7k74i+dSXSF3wLvF5SYII8/GUT/Ic+fycBR/DUQ==
+
 code-point-at@^1.0.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/code-point-at/-/code-point-at-1.1.0.tgz#0d070b4d043a5bea33a2f1a40e2edb3d9a4ccf77"
@@ -3821,6 +3836,11 @@ commander@^4.1.1:
   resolved "https://registry.yarnpkg.com/commander/-/commander-4.1.1.tgz#9fd602bd936294e9e9ef46a3f4d6964044b18068"
   integrity sha512-NOKm8xhkzAjzFx8B2v5OAHT+u5pRQc2UCa2Vq9jYL/31o2wi9mxBA7LIFs3sV5VSC49z6pEhfbMULvShKj26WA==
 
+commander@^6.2.1:
+  version "6.2.1"
+  resolved "https://registry.yarnpkg.com/commander/-/commander-6.2.1.tgz#0792eb682dfbc325999bb2b84fddddba110ac73c"
+  integrity sha512-U7VdrJFnJgo4xjrHpTzu0yrHPGImdsmD95ZlgYSEajAn2JKzDhDTPG9kBTefmObL2w/ngeZnilk+OV9CG3d7UA==
+
 commondir@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/commondir/-/commondir-1.0.1.tgz#ddd800da0c66127393cca5950ea968a3aaf1253b"
@@ -4000,7 +4020,7 @@ cosmiconfig@^5.0.0:
     js-yaml "^3.13.1"
     parse-json "^4.0.0"
 
-cosmiconfig@^7.0.0:
+cosmiconfig@^7.0.0, cosmiconfig@^7.0.1:
   version "7.0.1"
   resolved "https://registry.yarnpkg.com/cosmiconfig/-/cosmiconfig-7.0.1.tgz#714d756522cace867867ccb4474c5d01bbae5d6d"
   integrity sha512-a1YWNUV2HwGimB7dU2s1wUMurNKjpx60HxBB6xUM8Re+2s1g1IIfJvFR0/iCF+XHdE0GMTKTuLR32UQff4TEyQ==
@@ -5514,7 +5534,7 @@ fast-glob@^2.0.2:
     merge2 "^1.2.3"
     micromatch "^3.1.10"
 
-fast-glob@^3.2.5, fast-glob@^3.2.9:
+fast-glob@^3.2.5, fast-glob@^3.2.7, fast-glob@^3.2.9:
   version "3.2.11"
   resolved "https://registry.yarnpkg.com/fast-glob/-/fast-glob-3.2.11.tgz#a1172ad95ceb8a16e20caa5c5e56480e5129c1d9"
   integrity sha512-xrO3+1bxSo3ZVHAnqzyuewYT6aMFHRAd4Kcs92MAonjwQZLsK9d0SF1IyQ3k5PoirxTW0Oe/RqFgMQ6TcNE5Ew==
@@ -7978,7 +7998,7 @@ json5@^1.0.1:
   dependencies:
     minimist "^1.2.0"
 
-json5@^2.1.2, json5@^2.2.1:
+json5@^2.1.2, json5@^2.1.3, json5@^2.2.1:
   version "2.2.1"
   resolved "https://registry.yarnpkg.com/json5/-/json5-2.2.1.tgz#655d50ed1e6f95ad1a3caababd2b0efda10b395c"
   integrity sha512-1hqLFMSrGHRHxav9q9gNjJ5EXznIxGVO09xQRrwplcS8qs28pZ8s8hupZAmqDwZUmVZ2Qb2jnyPOWcDH8m8dlA==
@@ -9556,6 +9576,11 @@ path-browserify@0.0.1:
   resolved "https://registry.yarnpkg.com/path-browserify/-/path-browserify-0.0.1.tgz#e6c4ddd7ed3aa27c68a20cc4e50e1a4ee83bbc4a"
   integrity sha512-BapA40NHICOS+USX9SN4tyhq+A2RrN/Ws5F0Z5aMHDp98Fl86lX8Oti8B7uN93L4Ifv4fHOEA+pQw87gmMO/lQ==
 
+path-browserify@^1.0.1:
+  version "1.0.1"
+  resolved "https://registry.yarnpkg.com/path-browserify/-/path-browserify-1.0.1.tgz#d98454a9c3753d5790860f16f68867b9e46be1fd"
+  integrity sha512-b7uo2UCUOYZcnF/3ID0lulOJi/bafxa1xPe7ZPsammBSpjSWQkjNxlt635YGS2MiR9GjvuXCtz2emr3jbsz98g==
+
 path-dirname@^1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/path-dirname/-/path-dirname-1.0.2.tgz#cc33d24d525e099a5388c0336c6e32b9160609e0"
@@ -12531,6 +12556,31 @@ trough@^1.0.0:
   resolved "https://registry.yarnpkg.com/trough/-/trough-1.0.5.tgz#b8b639cefad7d0bb2abd37d433ff8293efa5f406"
   integrity sha512-rvuRbTarPXmMb79SmzEp8aqXNKcK+y0XaB298IXueQ8I2PsrATcPBCSPyK/dDNa2iWOhKlfNnOjdAOTBU/nkFA==
 
+"true-myth@^4.1.0":
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/true-myth/-/true-myth-4.1.1.tgz#ff4ac9d5130276e34aa338757e2416ec19248ba2"
+  integrity sha512-rqy30BSpxPznbbTcAcci90oZ1YR4DqvKcNXNerG5gQBU2v4jk0cygheiul5J6ExIMrgDVuanv/MkGfqZbKrNNg==
+
+ts-morph@^13.0.1:
+  version "13.0.3"
+  resolved "https://registry.yarnpkg.com/ts-morph/-/ts-morph-13.0.3.tgz#c0c51d1273ae2edb46d76f65161eb9d763444c1d"
+  integrity sha512-pSOfUMx8Ld/WUreoSzvMFQG5i9uEiWIsBYjpU9+TTASOeUa89j5HykomeqVULm1oqWtBdleI3KEFRLrlA3zGIw==
+  dependencies:
+    "@ts-morph/common" "~0.12.3"
+    code-block-writer "^11.0.0"
+
+ts-prune@^0.10.3:
+  version "0.10.3"
+  resolved "https://registry.yarnpkg.com/ts-prune/-/ts-prune-0.10.3.tgz#b6c71a525543b38dcf947a7d3adfb7f9e8b91f38"
+  integrity sha512-iS47YTbdIcvN8Nh/1BFyziyUqmjXz7GVzWu02RaZXqb+e/3Qe1B7IQ4860krOeCGUeJmterAlaM2FRH0Ue0hjw==
+  dependencies:
+    commander "^6.2.1"
+    cosmiconfig "^7.0.1"
+    json5 "^2.1.3"
+    lodash "^4.17.21"
+    "true-myth" "^4.1.0"
+    ts-morph "^13.0.1"
+
 tsconfig-paths@^3.14.1:
   version "3.14.1"
   resolved "https://registry.yarnpkg.com/tsconfig-paths/-/tsconfig-paths-3.14.1.tgz#ba0734599e8ea36c862798e920bcf163277b137a"