feat(essentials): add preferReuse setting

.yarn/versions/efc24e59.yml

@@ -0,0 +1,23 @@
+releases:
+  "@yarnpkg/cli": minor
+  "@yarnpkg/plugin-essentials": minor
+
+declined:
+  - "@yarnpkg/plugin-compat"
+  - "@yarnpkg/plugin-constraints"
+  - "@yarnpkg/plugin-dlx"
+  - "@yarnpkg/plugin-init"
+  - "@yarnpkg/plugin-interactive-tools"
+  - "@yarnpkg/plugin-nm"
+  - "@yarnpkg/plugin-npm-cli"
+  - "@yarnpkg/plugin-pack"
+  - "@yarnpkg/plugin-patch"
+  - "@yarnpkg/plugin-pnp"
+  - "@yarnpkg/plugin-pnpm"
+  - "@yarnpkg/plugin-stage"
+  - "@yarnpkg/plugin-typescript"
+  - "@yarnpkg/plugin-version"
+  - "@yarnpkg/plugin-workspace-tools"
+  - "@yarnpkg/builder"
+  - "@yarnpkg/core"
+  - "@yarnpkg/doctor"

packages/acceptance-tests/pkg-tests-specs/sources/commands/add.test.ts

@@ -1,4 +1,5 @@
 import {Filename, PortablePath, ppath, xfs} from '@yarnpkg/fslib';
+import {yarn}                               from 'pkg-tests-core';
 
 const {
   tests: {getPackageDirectoryPath},
@@ -253,6 +254,24 @@ describe(`Commands`, () => {
       }),
     );
 
+    test(
+      `it should not upgrade the existing dependency in the current project for preferReuse`,
+      makeTemporaryEnv({
+        devDependencies: {
+          [`no-deps`]: `1.0.0`,
+        },
+      }, async ({path, run, source}) => {
+        await yarn.writeConfiguration(path, {preferReuse: true});
+        await run(`add`, `no-deps`);
+
+        await expect(xfs.readJsonPromise(`${path}/package.json` as PortablePath)).resolves.toMatchObject({
+          devDependencies: {
+            [`no-deps`]: `1.0.0`,
+          },
+        });
+      }),
+    );
+
     test(
       `it should add a new peer dependency to the current project`,
       makeTemporaryEnv({}, async ({path, run, source}) => {

packages/gatsby/static/configuration/yarnrc.json

@@ -662,6 +662,12 @@
       "type": "boolean",
       "default": false
     },
+    "preferReuse": {
+      "_package": "@yarnpkg/core",
+      "description": "If true, `yarn add` command will reuse the most common dependency range in other workspaces (if pertinent).",
+      "type": "boolean",
+      "default": false
+    },
     "preferTruncatedLines": {
       "_package": "@yarnpkg/core",
       "description": "If true, Yarn will truncate lines that would go beyond the size of the terminal. If progress bars are disabled, lines will never be truncated. Forgettable lines (e.g. the fetch step logs) are always truncated.",

packages/plugin-essentials/sources/commands/add.ts

@@ -133,19 +133,23 @@ export default class AddCommand extends BaseCommand {
 
     const fixed = this.fixed;
     const interactive = this.interactive ?? configuration.get(`preferInteractive`);
+    const reuse = interactive || configuration.get(`preferReuse`);
 
     const modifier = suggestUtils.getModifier(this, project);
 
     const strategies = [
-      ...interactive ? [
-        suggestUtils.Strategy.REUSE,
-      ] : [],
+      reuse ?
+        suggestUtils.Strategy.REUSE
+        : undefined,
+
       suggestUtils.Strategy.PROJECT,
-      ...this.cached ? [
-        suggestUtils.Strategy.CACHE,
-      ] : [],
+
+      this.cached ?
+        suggestUtils.Strategy.CACHE
+        : undefined,
+
       suggestUtils.Strategy.LATEST,
-    ];
+    ].filter(isStrategy);
 
     const maxResults = interactive
       ? Infinity
@@ -323,6 +327,10 @@ export default class AddCommand extends BaseCommand {
   }
 }
 
+function isStrategy(strategy?: suggestUtils.Strategy): strategy is suggestUtils.Strategy {
+  return typeof strategy !== `undefined`;
+}
+
 function suggestTarget(workspace: Workspace, ident: Ident, {dev, peer, preferDev, optional}: {dev: boolean, peer: boolean, preferDev: boolean, optional: boolean}) {
   const hasRegular = workspace.manifest[suggestUtils.Target.REGULAR].has(ident.identHash);
   const hasDev = workspace.manifest[suggestUtils.Target.DEVELOPMENT].has(ident.identHash);

packages/yarnpkg-core/sources/Configuration.ts

@@ -262,6 +262,11 @@ export const coreDefinitions: {[coreSettingName: string]: SettingsDefinition} =
     type: SettingsType.BOOLEAN,
     default: false,
   },
+  preferReuse: {
+    description: `If true, the CLI will use the hightest version of existing, latest for new dependencies`,
+    type: SettingsType.BOOLEAN,
+    default: false,
+  },
   preferTruncatedLines: {
     description: `If true, the CLI will truncate lines that would go beyond the size of the terminal`,
     type: SettingsType.BOOLEAN,