Phase 5: add rename and find usages

src/main/gen/dev/hgh/jai/psi/impl/JaiDeclNameImpl.java

@@ -8,12 +8,12 @@ import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiElementVisitor;
 import com.intellij.psi.util.PsiTreeUtil;
 import static dev.hgh.jai.psi.JaiTypes.*;
-import com.intellij.extapi.psi.ASTWrapperPsiElement;
+import dev.hgh.jai.psi.mixin.JaiNamedElementMixin;
 import dev.hgh.jai.psi.*;
 
-public class JaiDeclNameImpl extends ASTWrapperPsiElement implements JaiDeclName {
+public class JaiDeclNameImpl extends JaiNamedElementMixin implements JaiDeclName {
 
-  public JaiDeclNameImpl(@NotNull ASTNode node) {
+  public JaiDeclNameImpl(ASTNode node) {
     super(node);
   }
 

src/main/grammar/Jai.bnf

@@ -227,6 +227,7 @@ private declModifier_ ::= <<dirWithBlock>> directiveFlag_* block
 private usingModifier_ ::= 'using' [directiveFlag_ [<<exprNoAssign>>]]
 declNames ::= declName (['='] ',' declName ['='])* ['=']
 declName ::= ['`'] (IDENT | keywordAsName_)
+           { mixin="dev.hgh.jai.psi.mixin.JaiNamedElementMixin" }
 private declTail_ ::= ':' [<<exprNoAssign>>] procModifier* [',' assignTargets_] [('=' | ':') initializerList_]
                     | ':=' initializerList_
                     | '::' initializerList_

src/main/kotlin/dev/hgh/jai/findusages/JaiFindUsagesProvider.kt

@@ -0,0 +1,41 @@
+package dev.hgh.jai.findusages
+
+import com.intellij.lang.cacheBuilder.DefaultWordsScanner
+import com.intellij.lang.cacheBuilder.WordsScanner
+import com.intellij.lang.findUsages.FindUsagesProvider
+import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiNameIdentifierOwner
+import com.intellij.psi.PsiNamedElement
+import com.intellij.psi.tree.TokenSet
+import dev.hgh.jai.lexer.JaiLexer
+import dev.hgh.jai.lexer.JaiTokenTypes
+import dev.hgh.jai.psi.JaiRefExpr
+
+/** Supplies word indexing and descriptions for Jai declaration usages. */
+class JaiFindUsagesProvider : FindUsagesProvider {
+    override fun getWordsScanner(): WordsScanner =
+        DefaultWordsScanner(
+            JaiLexer(),
+            TokenSet.create(JaiTokenTypes.IDENT),
+            JaiTokenTypes.COMMENTS,
+            JaiTokenTypes.STRINGS,
+        )
+
+    override fun canFindUsagesFor(psiElement: PsiElement): Boolean = psiElement is PsiNameIdentifierOwner || psiElement is JaiRefExpr
+
+    override fun getHelpId(psiElement: PsiElement): String? = null
+
+    override fun getType(element: PsiElement): String =
+        if (element is PsiNameIdentifierOwner || element is JaiRefExpr) {
+            "Jai declaration"
+        } else {
+            ""
+        }
+
+    override fun getDescriptiveName(element: PsiElement): String = (element as? PsiNamedElement)?.name ?: element.text
+
+    override fun getNodeText(
+        element: PsiElement,
+        useFullName: Boolean,
+    ): String = element.text
+}

src/main/kotlin/dev/hgh/jai/psi/JaiPsiElementFactory.kt

@@ -0,0 +1,23 @@
+package dev.hgh.jai.psi
+
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiFileFactory
+import com.intellij.psi.util.PsiTreeUtil
+import dev.hgh.jai.JaiLanguage
+import dev.hgh.jai.lexer.JaiTokenTypes
+
+/** Creates small Jai PSI fragments for AST replacements used by rename refactoring. */
+object JaiPsiElementFactory {
+    fun createIdentifier(
+        project: Project,
+        name: String,
+    ): PsiElement {
+        val file = PsiFileFactory.getInstance(project).createFileFromText("rename.jai", JaiLanguage, "$name :: 0;")
+        val declarationName =
+            PsiTreeUtil.findChildOfType(file, JaiDeclName::class.java)
+                ?: error("Could not parse a Jai declaration name for '$name'")
+        return declarationName.node.findChildByType(JaiTokenTypes.IDENT)?.psi
+            ?: error("Jai name '$name' is not an identifier")
+    }
+}

src/main/kotlin/dev/hgh/jai/psi/mixin/JaiNamedElementMixin.kt

@@ -0,0 +1,28 @@
+package dev.hgh.jai.psi.mixin
+
+import com.intellij.extapi.psi.ASTWrapperPsiElement
+import com.intellij.lang.ASTNode
+import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiNameIdentifierOwner
+import dev.hgh.jai.lexer.JaiTokenTypes
+import dev.hgh.jai.psi.JaiPsiElementFactory
+
+/** Gives declaration names the standard PSI naming contract used by rename/find-usages. */
+abstract class JaiNamedElementMixin(
+    node: ASTNode,
+) : ASTWrapperPsiElement(node),
+    PsiNameIdentifierOwner {
+    override fun getNameIdentifier(): PsiElement? = node.findChildByType(JaiTokenTypes.IDENT)?.psi
+
+    override fun getName(): String? = nameIdentifier?.text
+
+    override fun setName(name: String): PsiElement {
+        val identifier = nameIdentifier ?: return this
+        identifier.replace(JaiPsiElementFactory.createIdentifier(project, name))
+        return this
+    }
+
+    override fun getNavigationElement(): PsiElement = nameIdentifier ?: this
+
+    override fun getTextOffset(): Int = nameIdentifier?.textOffset ?: super.getTextOffset()
+}

src/main/kotlin/dev/hgh/jai/refactoring/JaiNamesValidator.kt

@@ -0,0 +1,26 @@
+package dev.hgh.jai.refactoring
+
+import com.intellij.lang.refactoring.NamesValidator
+import com.intellij.openapi.project.Project
+import dev.hgh.jai.lexer.JaiTokenTypes
+
+/** Applies Jai's ASCII identifier and keyword rules to rename input. */
+class JaiNamesValidator : NamesValidator {
+    override fun isKeyword(
+        name: String,
+        project: Project?,
+    ): Boolean = name in JaiTokenTypes.KEYWORD_MAP
+
+    override fun isIdentifier(
+        name: String,
+        project: Project?,
+    ): Boolean {
+        if (name.isEmpty() || isKeyword(name, project)) return false
+        if (!isIdentifierStart(name.first())) return false
+        return name.drop(1).all(::isIdentifierPart)
+    }
+
+    private fun isIdentifierStart(character: Char): Boolean = character in 'a'..'z' || character in 'A'..'Z' || character == '_'
+
+    private fun isIdentifierPart(character: Char): Boolean = isIdentifierStart(character) || character in '0'..'9'
+}

src/main/kotlin/dev/hgh/jai/refactoring/JaiRefactoringSupportProvider.kt

@@ -0,0 +1,14 @@
+package dev.hgh.jai.refactoring
+
+import com.intellij.lang.refactoring.RefactoringSupportProvider
+import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiNameIdentifierOwner
+import dev.hgh.jai.JaiLanguage
+
+/** Enables standard and in-place rename for Jai declaration names. */
+class JaiRefactoringSupportProvider : RefactoringSupportProvider() {
+    override fun isMemberInplaceRenameAvailable(
+        elementToRename: PsiElement,
+        context: PsiElement?,
+    ): Boolean = elementToRename is PsiNameIdentifierOwner && elementToRename.language == JaiLanguage
+}

src/main/kotlin/dev/hgh/jai/reference/JaiReferenceContributor.kt

@@ -22,6 +22,7 @@ import dev.hgh.jai.psi.JaiDeclName
 import dev.hgh.jai.psi.JaiDeclaration
 import dev.hgh.jai.psi.JaiDirectiveExpr
 import dev.hgh.jai.psi.JaiLiteralExpr
+import dev.hgh.jai.psi.JaiPsiElementFactory
 import dev.hgh.jai.psi.JaiRefExpr
 
 /** Adds file references for directives and symbol references for Jai identifiers. */
@@ -106,6 +107,12 @@ private class JaiSymbolReference(
 ) : PsiReferenceBase<JaiRefExpr>(sourceElement, TextRange(0, sourceElement.textLength), true) {
     override fun resolve(): PsiElement? = JaiSymbolResolver.resolve(sourceElement)
 
+    override fun handleElementRename(newElementName: String): PsiElement {
+        val identifier = sourceElement.node.findChildByType(JaiTokenTypes.IDENT)?.psi ?: return sourceElement
+        identifier.replace(JaiPsiElementFactory.createIdentifier(sourceElement.project, newElementName))
+        return sourceElement
+    }
+
     override fun getVariants(): Array<Any> = emptyArray()
 }
 

src/main/resources/META-INF/plugin.xml

@@ -41,6 +41,15 @@
         <completion.contributor
             language="Jai"
             implementationClass="dev.hgh.jai.completion.JaiCompletionContributor"/>
+        <lang.refactoringSupport
+            language="Jai"
+            implementationClass="dev.hgh.jai.refactoring.JaiRefactoringSupportProvider"/>
+        <lang.namesValidator
+            language="Jai"
+            implementationClass="dev.hgh.jai.refactoring.JaiNamesValidator"/>
+        <lang.findUsagesProvider
+            language="Jai"
+            implementationClass="dev.hgh.jai.findusages.JaiFindUsagesProvider"/>
     </extensions>
 
 </idea-plugin>

src/test/kotlin/dev/hgh/jai/findusages/JaiFindUsagesTest.kt

@@ -0,0 +1,37 @@
+package dev.hgh.jai.findusages
+
+import com.intellij.psi.search.searches.ReferencesSearch
+import com.intellij.psi.util.PsiTreeUtil
+import com.intellij.testFramework.fixtures.BasePlatformTestCase
+import dev.hgh.jai.psi.JaiDeclName
+
+class JaiFindUsagesTest : BasePlatformTestCase() {
+    fun testFindUsagesActionFindsProcedureReference() {
+        val usages = myFixture.testFindUsages("Declaration.jai", "Usage.jai")
+
+        assertEquals(1, usages.size)
+    }
+
+    fun testFindsProcedureReferencesFromDeclaration() {
+        val source =
+            myFixture.addFileToProject(
+                "find-usages.jai",
+                """
+                helper :: () {}
+                first :: () { helper(); }
+                second :: () { helper(); }
+                """.trimIndent(),
+            )
+        val declaration =
+            PsiTreeUtil
+                .findChildrenOfType(source, JaiDeclName::class.java)
+                .single { it.text == "helper" }
+
+        val usages = ReferencesSearch.search(declaration).findAll()
+
+        assertEquals(2, usages.size)
+        assertTrue(usages.all { it.element.text == "helper" })
+    }
+
+    override fun getTestDataPath(): String = "src/test/testData/findusages"
+}

src/test/kotlin/dev/hgh/jai/refactoring/JaiRenameTest.kt

@@ -0,0 +1,59 @@
+package dev.hgh.jai.refactoring
+
+import com.intellij.psi.PsiNameIdentifierOwner
+import com.intellij.testFramework.fixtures.BasePlatformTestCase
+
+class JaiRenameTest : BasePlatformTestCase() {
+    fun testDeclarationNamesParticipateInRename() {
+        myFixture.configureByText(
+            "rename.jai",
+            """
+            helper<caret> :: () {}
+            main :: () { helper(); }
+            """.trimIndent(),
+        )
+
+        val declaration = myFixture.elementAtCaret
+
+        assertTrue("declaration name should be a named PSI element", declaration is PsiNameIdentifierOwner)
+        assertEquals("helper", (declaration as PsiNameIdentifierOwner).name)
+    }
+
+    fun testRenameProcedureUpdatesSameFileReferences() {
+        myFixture.configureByText(
+            "rename.jai",
+            """
+            helper<caret> :: () {}
+            main :: () { helper(); }
+            """.trimIndent(),
+        )
+
+        myFixture.renameElementAtCaret("renamed")
+
+        myFixture.checkResult(
+            """
+            renamed :: () {}
+            main :: () { renamed(); }
+            """.trimIndent(),
+        )
+    }
+
+    fun testRenameTypeUpdatesTypeReferences() {
+        myFixture.configureByText(
+            "rename-type.jai",
+            """
+            Point<caret> :: struct { x: int; }
+            use_point :: (point: Point) -> int { return point.x; }
+            """.trimIndent(),
+        )
+
+        myFixture.renameElementAtCaret("Coordinate")
+
+        myFixture.checkResult(
+            """
+            Coordinate :: struct { x: int; }
+            use_point :: (point: Coordinate) -> int { return point.x; }
+            """.trimIndent(),
+        )
+    }
+}

src/test/testData/findusages/Declaration.jai

@@ -0,0 +1 @@
+helper<caret> :: () {}

src/test/testData/findusages/Usage.jai

@@ -0,0 +1,2 @@
+#load "Declaration.jai";
+main :: () { helper(); }