fix: warning should not result in non-zero exit code (#1872)

Co-authored-by: James George <[email protected]>

Author: snitin315

README.md

@@ -102,7 +102,7 @@ You can read more about [Scaffolding](https://webpack.js.org/guides/scaffolding)
 | Exit Code | Description                                        |
 | --------- | -------------------------------------------------- |
 | `0`       | Success                                            |
-| `1`       | Warnings/Errors from webpack                       |
+| `1`       | Errors from webpack                                |
 | `2`       | Configuration/options problem or an internal error |
 
 ## Contributing and Internal Documentation

packages/webpack-cli/lib/utils/Compiler.js

@@ -53,7 +53,7 @@ class Compiler {
             logger.error(err.stack || err);
             process.exit(1); // eslint-disable-line
         }
-        if (!outputOptions.watch && (stats.hasErrors() || stats.hasWarnings())) {
+        if (!outputOptions.watch && stats.hasErrors()) {
             process.exitCode = 1;
         }
         if (outputOptions.json === true) {

test/loader/warning-test/loader-warning.test.js

@@ -8,6 +8,6 @@ describe('loader warning test', () => {
 
         expect(stdout).toContain('[1 warning]');
         expect(stdout).toContain('This is a warning');
-        expect(exitCode).not.toEqual(0);
+        expect(exitCode).toEqual(0);
     });
 });

test/loader/warning-test/webpack.config.js

@@ -27,4 +27,7 @@ module.exports = {
             'my-loader': require.resolve('./my-loader'),
         },
     },
+    performance: {
+        hints: 'warning',
+    },
 };