Refactoring of custom errors, drop SyntaxError from export

csstree · Jan 22, 2020 · ab09af1 · ab09af1
1 parent 3355b15
commit ab09af1
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Showing 8 changed files with 60 additions and 71 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -23,6 +23,8 @@
 - Removed `element()` specific parsing rules
 - Changed `String` node type to store decoded string value (and auto encode a value on serialize)
 - Changed `Url` node type to store decoded url value (and auto encode a value on serialize)
+- Removed `SyntaxError` (custom parse error class) from public API
+- Removed `parseError` field in parse `SyntaxError`
 
 ## 1.0.0-alpha.39 (December 5, 2019)
 

diff --git a/lib/utils/create-custom-error.js → lib/common/create-custom-error.js b/lib/utils/create-custom-error.js → lib/common/create-custom-error.js
@@ -4,14 +4,11 @@ module.exports = function createCustomError(name, message) {
     const error = Object.create(SyntaxError.prototype);
     const errorStack = new Error();
 
-    error.name = name;
-    error.message = message;
-
-    Object.defineProperty(error, 'stack', {
-        get: function() {
-            return (errorStack.stack || '').replace(/^(.+\n){1,3}/, name + ': ' + message + '\n');
+    return Object.assign(error, {
+        name,
+        message,
+        get stack() {
+            return (errorStack.stack || '').replace(/^(.+\n){1,3}/, `${name}: ${message}\n`);
         }
     });
-
-    return error;
 };
diff --git a/lib/definition-syntax/SyntaxError.js b/lib/definition-syntax/SyntaxError.js
@@ -1,14 +1,12 @@
-const createCustomError = require('../utils/create-custom-error');
+const createCustomError = require('../common/create-custom-error');
 
 module.exports = function SyntaxError(message, input, offset) {
-    const error = createCustomError('SyntaxError', message);
-
-    error.input = input;
-    error.offset = offset;
-    error.rawMessage = message;
-    error.message = error.rawMessage + '\n' +
-        '  ' + error.input + '\n' +
-        '--' + new Array((error.offset || error.input.length) + 1).join('-') + '^';
-
-    return error;
+    return Object.assign(createCustomError('SyntaxError', message), {
+        input,
+        offset,
+        rawMessage: message,
+        message: message + '\n' +
+            '  ' + input + '\n' +
+            '--' + new Array((offset || input.length) + 1).join('-') + '^'
+    });
 };
diff --git a/lib/lexer/error.js b/lib/lexer/error.js
@@ -1,9 +1,8 @@
-const createCustomError = require('../utils/create-custom-error');
+const createCustomError = require('../common/create-custom-error');
 const generate = require('../definition-syntax/generate');
 
 function fromMatchResult(matchResult) {
-    const tokens = matchResult.tokens;
-    const longestMatch = matchResult.longestMatch;
+    const { tokens, longestMatch } = matchResult;
     const node = longestMatch < tokens.length ? tokens[longestMatch].node : null;
     let mismatchOffset = -1;
     let entries = 0;
@@ -58,33 +57,33 @@ const SyntaxReferenceError = function(type, referenceName) {
     return error;
 };
 
-const MatchError = function(message, syntax, node, matchResult) {
-    const error = createCustomError('SyntaxMatchError', message);
+const MatchError = function(message, syntaxAst, node, matchResult) {
     const details = fromMatchResult(matchResult);
     const mismatchOffset = details.mismatchOffset || 0;
     const badNode = details.node || node;
     const end = getLocation(badNode, 'end');
     const start = details.last ? end : getLocation(badNode, 'start');
     const css = details.css;
+    const syntax = syntaxAst ? generate(syntaxAst) : '<generic>';
 
-    error.rawMessage = message;
-    error.syntax = syntax ? generate(syntax) : '<generic>';
-    error.css = css;
-    error.mismatchOffset = mismatchOffset;
-    error.loc = {
-        source: (badNode && badNode.loc && badNode.loc.source) || '<unknown>',
-        start,
-        end
-    };
-    error.line = start ? start.line : undefined;
-    error.column = start ? start.column : undefined;
-    error.offset = start ? start.offset : undefined;
-    error.message = message + '\n' +
-        '  syntax: ' + error.syntax + '\n' +
-        '   value: ' + (error.css || '<empty string>') + '\n' +
-        '  --------' + '-'.repeat(error.mismatchOffset) + '^';
-
-    return error;
+    return Object.assign(createCustomError('SyntaxMatchError', message), {
+        rawMessage: message,
+        syntax,
+        css,
+        mismatchOffset,
+        loc: {
+            source: (badNode && badNode.loc && badNode.loc.source) || '<unknown>',
+            start,
+            end
+        },
+        line: start ? start.line : undefined,
+        column: start ? start.column : undefined,
+        offset: start ? start.offset : undefined,
+        message: message + '\n' +
+            '  syntax: ' + syntax + '\n' +
+            '   value: ' + (css || '<empty string>') + '\n' +
+            '  --------' + '-'.repeat(mismatchOffset) + '^'
+    });
 };
 
 module.exports = {

diff --git a/lib/common/SyntaxError.js → lib/parser/SyntaxError.js b/lib/common/SyntaxError.js → lib/parser/SyntaxError.js
@@ -1,9 +1,9 @@
-const createCustomError = require('../utils/create-custom-error');
+const createCustomError = require('../common/create-custom-error');
 const MAX_LINE_LENGTH = 100;
 const OFFSET_CORRECTION = 60;
 const TAB_REPLACEMENT = '    ';
 
-function sourceFragment(error, extraLines) {
+function sourceFragment({ source, line, column }, extraLines) {
     function processLines(start, end) {
         return lines
             .slice(start, end)
@@ -12,12 +12,10 @@ function sourceFragment(error, extraLines) {
             ).join('\n');
     }
 
-    const lines = error.source.split(/\r\n?|\n|\f/);
-    const line = error.line;
+    const lines = source.split(/\r\n?|\n|\f/);
     const startLine = Math.max(1, line - extraLines) - 1;
     const endLine = Math.min(line + extraLines, lines.length + 1);
     const maxNumLength = Math.max(4, String(endLine).length) + 1;
-    let column = error.column;
     let cutLeft = 0;
 
     // column correction according to replaced tab before column
@@ -46,29 +44,21 @@ function sourceFragment(error, extraLines) {
 }
 
 module.exports = function SyntaxError(message, source, offset, line, column) {
-    const error = createCustomError('SyntaxError', message);
-
-    error.source = source;
-    error.offset = offset;
-    error.line = line;
-    error.column = column;
-
-    error.sourceFragment = extraLines => sourceFragment(error, isNaN(extraLines) ? 0 : extraLines);
-    Object.defineProperty(error, 'formattedMessage', {
-        get() {
+    const error = Object.assign(createCustomError('SyntaxError', message), {
+        source,
+        offset,
+        line,
+        column,
+        sourceFragment(extraLines) {
+            return sourceFragment({ source, line, column }, isNaN(extraLines) ? 0 : extraLines);
+        },
+        get formattedMessage() {
             return (
-                'Parse error: ' + error.message + '\n' +
-                sourceFragment(error, 2)
+                `Parse error: ${message}\n` +
+                sourceFragment({ source, line, column }, 2)
             );
         }
     });
 
-    // for backward capability
-    error.parseError = {
-        offset,
-        line,
-        column
-    };
-
     return error;
 };
diff --git a/lib/parser/create.js b/lib/parser/create.js
@@ -1,7 +1,7 @@
 const OffsetToLocation = require('../common/OffsetToLocation');
-const SyntaxError = require('../common/SyntaxError');
 const TokenStream = require('../common/TokenStream');
 const List = require('../common/List');
+const SyntaxError = require('./SyntaxError');
 const tokenize = require('../tokenizer');
 const { findWhiteSpaceStart, cmpChar, cmpStr } = require('../tokenizer/utils');
 const NAME = require('../tokenizer/names');
@@ -306,6 +306,7 @@ module.exports = function createParser(config) {
     };
 
     return Object.assign(parse, {
+        SyntaxError,
         config: parser.config
     });
 };
diff --git a/lib/syntax/create.js b/lib/syntax/create.js
@@ -1,5 +1,4 @@
 const List = require('../common/List');
-const SyntaxError = require('../common/SyntaxError');
 const TokenStream = require('../common/TokenStream');
 const Lexer = require('../lexer/Lexer');
 const definitionSyntax = require('../definition-syntax');
@@ -23,7 +22,6 @@ function createSyntax(config) {
 
     const syntax = {
         List,
-        SyntaxError,
         TokenStream,
         Lexer,
 

diff --git a/test/parse.js b/test/parse.js
@@ -12,15 +12,19 @@ function createParseErrorTest(name, test, options) {
             () => parse(test.source, options),
             (e) => {
                 error = e;
-                if (e.parseError) {
+                if (e instanceof parse.SyntaxError === false) {
                     return true;
                 }
             },
             'Should be a CSS parse error'
         );
 
         assert.equal(error.message, test.error);
-        assert.deepEqual(error.parseError, test.position);
+        assert.deepEqual({
+            offset: error.offset,
+            line: error.line,
+            column: error.column
+        }, test.position);
     });
 }