Add highlighting for kewords with special symbols (#312)

eclipse-langium · Dec 2, 2021 · c259b68 · c259b68
1 parent 49bf240
commit c259b68
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Showing 2 changed files with 36 additions and 3 deletions.
diff --git a/packages/generator-langium/langium-template/src/language-server/language-id.langium b/packages/generator-langium/langium-template/src/language-server/language-id.langium
@@ -1,13 +1,13 @@
 grammar <%= LanguageName %>
 
-Model:
+entry Model:
     (persons+=Person | greetings+=Greeting)*;
 
 Person:
     'person' name=ID;
 
 Greeting:
-    'Hello' person=[Person|ID] '!';
+    'Hello' person=[Person:ID] '!';
 
 hidden terminal WS: /\s+/;
 terminal ID: /[_a-zA-Z][\w_]*/;

diff --git a/packages/langium-cli/src/generator/textmate-generator.ts b/packages/langium-cli/src/generator/textmate-generator.ts
@@ -118,12 +118,45 @@ function getControlKeywords(grammar: langium.Grammar, pack: LangiumConfig): Patt
     const regex = /[A-Za-z]/;
     const controlKeywords = collectKeywords(grammar).filter(kw => regex.test(kw));
     const keywords = controlKeywords.map(escapeRegExp);
+    const groups = groupKeywords(keywords);
     return {
         'name': `keyword.control.${pack.languageId}`,
-        'match': `\\b(${keywords.join('|')})\\b`
+        'match': groups.join('|')
     };
 }
 
+function groupKeywords(keywords: string[]): string[] {
+    const groups: {
+        letter: string[],
+        leftSpecial: string[],
+        rightSpecial: string[],
+        special: string[]
+    } = {letter: [], leftSpecial: [], rightSpecial: [], special: []};
+
+    keywords.forEach(keyword => {
+        if (/\w/.test(keyword[0])) {
+            if (/\w/.test(keyword[keyword.length - 1])) {
+                groups.letter.push(keyword);
+            } else {
+                groups.rightSpecial.push(keyword);
+            }
+        } else {
+            if ((/\w/).test(keyword[keyword.length - 1])) {
+                groups.leftSpecial.push(keyword);
+            } else {
+                groups.special.push(keyword);
+            }
+        }
+    });
+
+    const res = [];
+    if (groups.letter.length) res.push(`\\b(${groups.letter.join('|')})\\b`);
+    if (groups.leftSpecial.length) res.push(`\\B(${groups.leftSpecial.join('|')})\\b`);
+    if (groups.rightSpecial.length) res.push(`\\b(${groups.rightSpecial.join('|')})\\B`);
+    if (groups.special.length) res.push(`\\B(${groups.special.join('|')})\\B`);
+    return res;
+}
+
 function getStringPatterns(grammar: langium.Grammar, pack: LangiumConfig): Pattern[] {
     const terminals = langium.stream(grammar.rules).filter(langium.isTerminalRule);
     const stringTerminal = terminals.find(e => e.name.toLowerCase() === 'string');