Enable processing of further plugins

examples/samples/unformatted.json

@@ -0,0 +1,3 @@
+	{
+  "hello":  "world"
+ } 

src/index.js

@@ -30,6 +30,7 @@ const AllowComments = 'allowComments';
 const fileLintResults = {};
 const fileComments = {};
 const fileDocuments = {};
+const fileLengths = {};
 
 const getSignature = problem =>
     `${problem.range.start.line} ${problem.range.start.character} ${problem.message}`;
@@ -104,6 +105,30 @@ const errorSignature = err =>
 
 const getErrorCode = _.pipe(_.get('ruleId'), _.split('/'), _.last);
 
+const preprocessorPlaceholder = '___';
+const preprocessorTemplate = `JSON.stringify(${preprocessorPlaceholder})`;
+
+function mapFix(fix, fileLength, prefixLength, suffix) {
+    let text = fix.text;
+    // We have to map the fix in such a way, that we account for the removed prefix and suffix.
+    let range = fix.range.map(location => location - prefixLength);
+    // For the suffix we have three cases:
+    // 1) The fix ends before the suffix => nothing left to do
+    if (range[0] >= fileLength + suffix.length) {
+        // 2) The fix starts after the suffix (for example concerning the last line break)
+        range = range.map(location => location - suffix.length);
+    } else if (range[1] >= fileLength) {
+        // 3) The fix intersects the suffix
+        range[1] = Math.max(range[1] - suffix.length, fileLength);
+        // in that case we have to delete the suffix also from the fix text.
+        const suffixPosition = text.lastIndexOf(suffix);
+        if (suffixPosition >= 0) {
+            text = text.slice(0, suffixPosition) + text.slice(suffixPosition + suffix.length);
+        }
+    }
+    return {range, text};
+}
+
 const processors = {
     '.json': {
         preprocess: function(text, fileName) {
@@ -112,12 +137,27 @@ const processors = {
             const parsed = jsonServiceHandle.parseJSONDocument(textDocument);
             fileLintResults[fileName] = getDiagnostics(parsed);
             fileComments[fileName] = parsed.comments;
-            return ['']; // sorry nothing ;)
+
+            const [, eol = ''] = text.match(/([\n\r]*)$/);
+            fileLengths[fileName] = text.length - eol.length;
+            return [
+                preprocessorTemplate.replace(
+                    preprocessorPlaceholder,
+                    text.slice(0, fileLengths[fileName])
+                ) + eol
+            ];
         },
         postprocess: function(messages, fileName) {
             const textDocument = fileDocuments[fileName];
+            const fileLength = fileLengths[fileName];
             delete fileLintResults[fileName];
             delete fileComments[fileName];
+
+            const prefixLength = preprocessorTemplate.indexOf(preprocessorPlaceholder);
+            const suffix = preprocessorTemplate.slice(
+                prefixLength + preprocessorPlaceholder.length
+            );
+
             return _.pipe(
                 _.first,
                 _.groupBy(errorSignature),
@@ -144,9 +184,23 @@ const processors = {
                         endColumn: error.endColumn + 1
                     });
                 }),
+                _.mapValues(error => {
+                    if (_.startsWith('json/', error.ruleId)) return error;
+
+                    const newError = _.assign(error, {
+                        column: error.column - (error.line === 1 ? prefixLength : 0),
+                        endColumn: error.endColumn - (error.endLine === 1 ? prefixLength : 0)
+                    });
+                    if (error.fix) {
+                        newError.fix = mapFix(error.fix, fileLength, prefixLength, suffix);
+                    }
+
+                    return newError;
+                }),
                 _.values
             )(messages);
-        }
+        },
+        supportsAutofix: true
     }
 };
 

test/.eslintrc.with-prettier.json

@@ -0,0 +1,12 @@
+{
+    "plugins": ["self", "prettier"],
+    "rules": {
+        "prettier/prettier": ["error", {
+            "tabWidth": 4,
+            "useTabs": true,
+            "trailingComma": "all",
+            "singleQuote": true,
+            "endOfLine": "lf"
+        }]
+    }
+}

test/integration.test.js

@@ -5,11 +5,18 @@ const _ = require('lodash/fp');
 const SCOPE = 'self'; // (for test purpose only, relying the the eslint-plugin-self for tests)
 const scoped = rule => `${SCOPE}/${rule}`;
 
-function getLintResults(filename, eslintConfig) {
+function getLintResults(filename, eslintConfig, commands = []) {
     try {
         const results = execFileSync(
             'eslint',
-            ['--config', eslintConfig || 'custom.eslintrc.json', '--format', 'json', filename],
+            [
+                '--config',
+                eslintConfig || 'custom.eslintrc.json',
+                ...commands,
+                '--format',
+                'json',
+                filename
+            ],
             {
                 encoding: 'utf8',
                 stdio: 'pipe',
@@ -45,10 +52,9 @@ function validateInfringementExpectation(expected, actualSituation) {
         else expect(actualSituation).to.have.property(scoped(rule));
     }
     const allExpectedErrors = expected.map(_.pipe(_.split(':'), _.head, scoped));
-    expect(_.xor(_.keys(actualSituation), allExpectedErrors)).to.have.length(
-        0,
-        'Extra errors found'
-    );
+    // only check for errors generated by this plugin
+    const actualErrors = _.keys(actualSituation).filter(error => error.startsWith(scoped('')));
+    expect(_.xor(actualErrors, allExpectedErrors)).to.have.length(0, 'Extra errors found');
 }
 
 function validateFile(filename, config = {}) {
@@ -63,6 +69,15 @@ function validateFile(filename, config = {}) {
         expect(results.warningCount).to.equal(config.warningCount, 'invalid counr of warnings');
 }
 
+function validateFixes(filename, config = {}) {
+    const result = getLintResults(`samples/${filename}.json`, config.eslintrc, ['--fix-dry-run']);
+
+    expect(result.output).not.to.be.undefined;
+    if (config.fixedOutput !== undefined) {
+        expect(result.output).to.equal(config.fixedOutput);
+    }
+}
+
 describe('Integrations tests', function() {
     it('validate correct json', function() {
         validateFile('good-json', {errorCount: 0, warningCount: 0});
@@ -119,3 +134,12 @@ describe('Integrations tests with config', function() {
         });
     });
 });
+
+describe('Integrations tests with Prettier', function() {
+    it('prettifies JSON file', function() {
+        validateFixes('unformatted', {
+            eslintrc: '.eslintrc.with-prettier.json',
+            fixedOutput: '{\n\t"hello": "world"\n}\n'
+        });
+    });
+});

test/unit.test.js

@@ -27,12 +27,13 @@ describe('plugin', function() {
     });
     describe('preprocess', function() {
         const preprocess = plugin.processors['.json'].preprocess;
-        it('should return the same text', function() {
+        it('should contain the text', function() {
             const fileName = 'whatever-the-name.js';
 
-            const newText = preprocess('whatever', fileName);
+            const text = 'whatever';
+            const newText = preprocess(text, fileName);
             assert.isArray(newText, 'preprocess should return array');
-            assert.strictEqual(newText[0], '');
+            assert.include(newText[0], text);
         });
     });
     describe('postprocess', function() {