Merge pull request #53 from kris7t/imports

Module and import resolution support

5 files changed, 84 insertions, 16 deletions

diff --git a/subprojects/frontend/src/editor/EditorTheme.ts b/subprojects/frontend/src/editor/EditorTheme.ts
index 1cad4a36..4978c7f7 100644
--- a/subprojects/frontend/src/editor/EditorTheme.ts
+++ b/subprojects/frontend/src/editor/EditorTheme.ts
@@ -40,7 +40,9 @@ function createTypeHashStyles(
 export default styled('div', {
   name: 'EditorTheme',
   shouldForwardProp: (propName) =>
-    propName !== 'showLineNumbers' && propName !== 'showActiveLine',
+    propName !== 'showLineNumbers' &&
+    propName !== 'showActiveLine' &&
+    propName !== 'colorIdentifiers',
 })<{
   showLineNumbers: boolean;
   showActiveLine: boolean;
@@ -126,7 +128,7 @@ export default styled('div', {
         color: theme.palette.text.secondary,
       },
     },
-    '.tok-problem-individual': {
+    '.tok-problem-atom': {
       '&, & .tok-variableName': {
         color: theme.palette.text.primary,
       },
diff --git a/subprojects/frontend/src/language/problem.grammar b/subprojects/frontend/src/language/problem.grammar
index ce3baa02..b69ee73f 100644
--- a/subprojects/frontend/src/language/problem.grammar
+++ b/subprojects/frontend/src/language/problem.grammar
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ * SPDX-FileCopyrightText: 2021-2024 The Refinery Authors <https://refinery.tools/>
  *
  * SPDX-License-Identifier: EPL-2.0
  */
@@ -22,13 +22,16 @@
 @top Problem { statement* }
 
 statement {
+  ImportStatement {
+    kw<"import"> ModuleName (kw<"as"> ModuleName)? "."
+  } |
   Assertion {
     kw<"default">? (NotOp | UnknownOp)? RelationName
     ParameterList<AssertionArgument>
     (":" Expr)? "."
   } |
   ProblemDeclaration {
-    kw<"problem"> QualifiedName "."
+    (ckw<"module"> | kw<"problem">) ModuleName "."
   } |
   ClassDefinition {
     kw<"abstract">? kw<"class"> RelationName
@@ -37,7 +40,7 @@ statement {
   } |
   EnumDefinition {
     kw<"enum"> RelationName
-    (EnumBody { "{" sep<",", IndividualNodeName> "}" } | ".")
+    (EnumBody { "{" sep<",", AtomNodeName> "}" } | ".")
   } |
   PredicateDefinition {
     (
@@ -56,8 +59,11 @@ statement {
   //  RuleName ParameterList<Parameter>?
   //  RuleBody { ":" sep<OrOp, Conjunction> "==>" sep<OrOp, Consequent> "." }
   //} |
-  IndividualDeclaration {
-    kw<"indiv"> sep<",", IndividualNodeName> "."
+  AtomDeclaration {
+    kw<"declare">? ckw<"atom"> sep<",", AtomNodeName> "."
+  } |
+  NodeDeclaration {
+    (kw<"declare"> | kw<"declare">? ckw<"multi">) sep<",", NodeName> "."
   } |
   ScopeDeclaration {
     kw<"scope"> sep<",", ScopeElement> "."
@@ -161,13 +167,15 @@ RelationName { QualifiedName ~name }
 
 //RuleName { QualifiedName }
 
-IndividualNodeName { QualifiedName }
+AtomNodeName { QualifiedName }
 
 VariableName[@dynamicPrecedence=10] { QualifiedName ~name }
 
 NodeName { QualifiedName }
 
-QualifiedName[implicitCompletion=true] { identifier ("::" identifier)* }
+ModuleName { QualifiedName }
+
+QualifiedName[implicitCompletion=true] { "::"? identifier (QualifiedNameSeparator "::" identifier)* }
 
 kw<term> { @specialize[@name={term},implicitCompletion=true]<identifier, term> }
 
@@ -181,6 +189,10 @@ sep1<separator, content> { content (separator content)* }
 
 @skip { LineComment | BlockComment | whitespace }
 
+@external tokens qualifiedNameSeparator from "./tokens" {
+  QualifiedNameSeparator
+}
+
 @tokens {
   whitespace { std.whitespace+ }
 
diff --git a/subprojects/frontend/src/language/problemLanguageSupport.ts b/subprojects/frontend/src/language/problemLanguageSupport.ts
index 2121e05f..14826363 100644
--- a/subprojects/frontend/src/language/problemLanguageSupport.ts
+++ b/subprojects/frontend/src/language/problemLanguageSupport.ts
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ * SPDX-FileCopyrightText: 2021-2024 The Refinery Authors <https://refinery.tools/>
  *
  * SPDX-License-Identifier: EPL-2.0
  */
@@ -27,7 +27,8 @@ const parserWithMetadata = parser.configure({
     styleTags({
       LineComment: t.lineComment,
       BlockComment: t.blockComment,
-      'problem class enum pred fn indiv scope': t.definitionKeyword,
+      'module problem class enum pred fn scope': t.definitionKeyword,
+      'import as declare atom multi': t.definitionKeyword,
       'abstract extends refers contains container opposite': t.modifier,
       'default error contained containment': t.modifier,
       'true false unknown error': t.keyword,
@@ -44,8 +45,9 @@ const parserWithMetadata = parser.configure({
       String: t.string,
       'RelationName/QualifiedName': t.typeName,
       // 'RuleName/QualifiedName': t.typeName,
-      'IndividualNodeName/QualifiedName': t.atom,
+      'AtomNodeName/QualifiedName': t.atom,
       'VariableName/QualifiedName': t.variableName,
+      'ModuleName/QualifiedName': t.typeName,
       '{ }': t.brace,
       '( )': t.paren,
       '[ ]': t.squareBracket,
@@ -54,7 +56,8 @@ const parserWithMetadata = parser.configure({
     }),
     indentNodeProp.add({
       ProblemDeclaration: indentDeclaration,
-      UniqueDeclaration: indentDeclaration,
+      AtomDeclaration: indentDeclaration,
+      NodeDeclaration: indentDeclaration,
       ScopeDeclaration: indentDeclaration,
       PredicateBody: indentPredicateOrRule,
       FunctionBody: indentPredicateOrRule,
@@ -70,7 +73,8 @@ const parserWithMetadata = parser.configure({
       // RuleBody: foldInside,
       Conjunction: foldConjunction,
       // Consequent: foldWholeNode,
-      UniqueDeclaration: foldDeclaration,
+      AtomDeclaration: foldDeclaration,
+      NodeDeclaration: foldDeclaration,
       ScopeDeclaration: foldDeclaration,
       BlockComment: foldBlockComment,
     }),
diff --git a/subprojects/frontend/src/language/tokens.ts b/subprojects/frontend/src/language/tokens.ts
new file mode 100644
index 00000000..b5d022f1
--- /dev/null
+++ b/subprojects/frontend/src/language/tokens.ts
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2018-2024 by Marijn Haverbeke <marijnh@gmail.com> and others
+ * Copyright (C) 2024 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: MIT AND EPL-2.0
+ *
+ * Based on the CSS tokenizer at
+ * https://github.com/lezer-parser/css/blob/790568c968a660a94bf0fbd97a86c66da1c529e5/src/tokens.js
+ */
+
+import { ExternalTokenizer } from '@lezer/lr';
+
+/* eslint-disable-next-line import/no-unresolved --
+  Synthetic import from `@lezer/generator/rollup` cannot be found by ESLint.
+*/
+import { QualifiedNameSeparator } from './problem.grammar.terms';
+
+const colon = 58;
+const underscore = 95;
+
+function isAlpha(ch: number) {
+  return (ch >= 65 && ch <= 90) || (ch >= 97 && ch <= 122) || ch >= 161;
+}
+
+function isDigit(ch: number) {
+  return ch >= 48 && ch <= 57;
+}
+
+function isIdentifier(ch: number) {
+  return isAlpha(ch) || isDigit(ch) || ch === underscore;
+}
+
+/* eslint-disable-next-line import/prefer-default-export --
+  Lezer requires a named export.
+*/
+export const qualifiedNameSeparator = new ExternalTokenizer((input) => {
+  if (input.peek(0) === colon && input.peek(1) === colon) {
+    const previous = input.peek(-1);
+    if (isIdentifier(previous)) {
+      // Inject an extra 0-length token into the token stream to let Lezer
+      // consume the `::` on its own. Explicitly consuming 2 characters here
+      // leads to inconsistent highlighting of qualified names.
+      input.acceptToken(QualifiedNameSeparator);
+    }
+  }
+});
diff --git a/subprojects/frontend/src/xtext/ContentAssistService.ts b/subprojects/frontend/src/xtext/ContentAssistService.ts
index ac8ab36a..d42dde14 100644
--- a/subprojects/frontend/src/xtext/ContentAssistService.ts
+++ b/subprojects/frontend/src/xtext/ContentAssistService.ts
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ * SPDX-FileCopyrightText: 2021-2024 The Refinery Authors <https://refinery.tools/>
  *
  * SPDX-License-Identifier: EPL-2.0
  */
@@ -108,7 +108,11 @@ function createCompletion(entry: ContentAssistEntry): Completion {
       boost = -90;
       break;
     default:
-      {
+      if (entry.proposal.startsWith('::')) {
+        // Move absolute names below relative names,
+        // they should only be preferred if no relative name is available.
+        boost = -60;
+      } else {
         // Penalize qualified names (vs available unqualified names).
         const extraSegments = entry.proposal.match(/::/g)?.length || 0;
         boost = Math.max(-5 * extraSegments, -50);