Fix #4449 Add a warning message when bibtex parser failed

src/completion/completer/citation.ts

@@ -1,5 +1,4 @@
 import * as vscode from 'vscode'
-import * as fs from 'fs'
 import { bibtexParser } from 'latex-utensils'
 import { lw } from '../../lw'
 import type { CitationField, CitationItem, CompletionArgs, CompletionItem, CompletionProvider } from '../../types'
@@ -245,9 +244,9 @@ async function parseBibFile(fileName: string) {
         return
     }
     const newEntry: CitationItem[] = []
-    const bibtex = fs.readFileSync(fileName).toString()
+    const bibtex = await lw.file.read(fileName)
     logger.log(`Parse BibTeX AST from ${fileName} .`)
-    const ast = await lw.parser.parse.bib(bibtex)
+    const ast = await lw.parser.parse.bib(vscode.Uri.file(fileName), bibtex ?? '')
     if (ast === undefined) {
         logger.log(`Parsed 0 bib entries from ${fileName}.`)
         lw.event.fire(lw.event.FileParsed, fileName)

src/core/commands.ts

@@ -424,7 +424,10 @@ export async function devParseBib() {
     if (vscode.window.activeTextEditor === undefined) {
         return
     }
-    const ast = await lw.parser.parse.bib(vscode.window.activeTextEditor.document.getText())
+    const ast = await lw.parser.parse.bib(
+        vscode.window.activeTextEditor.document.uri,
+        vscode.window.activeTextEditor.document.getText()
+    )
     return vscode.workspace.openTextDocument({content: JSON.stringify(ast, null, 2), language: 'json'}).then(doc => vscode.window.showTextDocument(doc))
 }
 

src/lint/bibtex-formatter.ts

@@ -58,7 +58,7 @@ async function formatDocument(document: vscode.TextDocument, sort: boolean, alig
     const columnOffset = range ? range.start.character : 0
 
     logger.log('Parse active BibTeX document for AST.')
-    const ast = await lw.parser.parse.bib(document.getText(range))
+    const ast = await lw.parser.parse.bib(document.uri, document.getText(range))
     if (ast === undefined) {
         return []
     }

src/outline/structure/bibtex.ts

@@ -28,7 +28,7 @@ export async function buildBibTeX(document: vscode.TextDocument): Promise<TeXEle
         return []
     }
     logger.log('Parse active BibTeX document for AST.')
-    const ast = await lw.parser.parse.bib(document.getText())
+    const ast = await lw.parser.parse.bib(document.uri, document.getText())
     if (ast === undefined) {
         return []
     }

src/parse/parser.ts

@@ -1,3 +1,4 @@
+import * as vscode from 'vscode'
 import * as path from 'path'
 import * as workerpool from 'workerpool'
 import type * as Ast from '@unified-latex/unified-latex-types'
@@ -12,6 +13,7 @@ import { latexLogParser } from './parser/latexlog'
 import { toString } from '../../../resources/unified.js'
 
 const logger = lw.log('Parser')
+const bibDiagnostics = vscode.languages.createDiagnosticCollection('BibTeX')
 
 export const parser = {
     bib,
@@ -42,12 +44,22 @@ async function reset() {
     return (await proxy).reset(getMacroDefs(), getEnvDefs())
 }
 
-async function bib(s: string, options?: bibtexParser.ParserOptions): Promise<bibtexParser.BibtexAst | undefined> {
-    const ast = await (await proxy).parseBibTeX(s, options)
-    if (ast instanceof Error) {
-        logger.logError('Error when parsing bib file.', ast)
+async function bib(uri: vscode.Uri, s: string): Promise<bibtexParser.BibtexAst | undefined> {
+    const ast = await (await proxy).parseBibTeX(s)
+    if (typeof ast === 'string') {
+        const err = JSON.parse(ast) as bibtexParser.SyntaxError
+        logger.log(`Error when parsing bib file: found ${err.found} from ${err.location.start.line}:${err.location.start.column} to ${err.location.end.line}:${err.location.end.column}.`)
+        bibDiagnostics.set(uri, [new vscode.Diagnostic(
+            new vscode.Range(
+                new vscode.Position(err.location.start.line - 1, err.location.start.column - 1),
+                new vscode.Position(err.location.end.line - 1, err.location.end.column - 1)
+            ),
+            `A BibTeX parsing error occurred. "${err.found}" is unexpected here. No BibTeX entries will be available.`,
+            vscode.DiagnosticSeverity.Warning
+        )])
         return undefined
     } else {
+        bibDiagnostics.set(uri, [])
         return ast
     }
 }

src/parse/parser/unified.ts

@@ -3,6 +3,7 @@ import type * as Ast from '@unified-latex/unified-latex-types'
 // import { getParser } from '@unified-latex/unified-latex-util-parse'
 // import { attachMacroArgs } from '@unified-latex/unified-latex-util-arguments'
 import { bibtexParser } from 'latex-utensils'
+import type { SyntaxError } from 'latex-utensils/out/types/src/pegjs/pegjs_types.js'
 
 // @ts-expect-error Load unified.js from /out/src/...
 import { getParser, attachMacroArgs } from '../../../../resources/unified.js'
@@ -26,12 +27,12 @@ function reset(macros: Ast.MacroInfoRecord, environments: Ast.EnvInfoRecord) {
     unifiedParser = getParser({ macros, environments, flags: { autodetectExpl3AndAtLetter: true } })
 }
 
-function parseBibTeX(s: string, options?: bibtexParser.ParserOptions): bibtexParser.BibtexAst | Error | undefined {
+function parseBibTeX(s: string): bibtexParser.BibtexAst | string | undefined {
     try {
-        return bibtexParser.parse(s, options)
+        return bibtexParser.parse(s)
     } catch (err) {
-        if (err instanceof Error) {
-            return err
+        if (bibtexParser.isSyntaxError(err)) {
+            return JSON.stringify(err)
         }
         return undefined
     }

test/units/11_parser_tex.test.ts

@@ -1,3 +1,4 @@
+import * as vscode from 'vscode'
 import * as path from 'path'
 import * as sinon from 'sinon'
 import { lw } from '../../src/lw'
@@ -26,7 +27,7 @@ describe(path.basename(__filename).split('.')[0] + ':', () => {
 
     describe('lw.parser->bib', () => {
         it('should parse BibTeX content', async () => {
-            const ast = await parser.bib('@article{key, author = "author"}')
+            const ast = await parser.bib(vscode.Uri.file('/main.bib'), '@article{key, author = "author"}')
 
             assert.ok(ast)
             assert.strictEqual(ast.content[0].entryType, 'article')
@@ -37,7 +38,7 @@ describe(path.basename(__filename).split('.')[0] + ':', () => {
         })
 
         it('should log error when parsing BibTeX content fails', async () => {
-            const ast = await parser.bib('@article{key, author = "author",')
+            const ast = await parser.bib(vscode.Uri.file('/main.bib'), '@article{key, author = "author",')
 
             assert.strictEqual(ast, undefined)
             assert.hasLog('Error when parsing bib file.')