[WIP] reuse a cached AST if available

Signed-off-by: David Thompson <[email protected]>
eclipse-jdtls · Jan 23, 2025 · 6a9559c · 6a9559c
1 parent 7be2137
commit 6a9559c
Show file tree

Hide file tree

Showing 8 changed files with 48 additions and 24 deletions.
diff --git a/org.eclipse.jdt.core.javac/src/org/eclipse/jdt/core/dom/DOMCompletionEngineProvider.java b/org.eclipse.jdt.core.javac/src/org/eclipse/jdt/core/dom/DOMCompletionEngineProvider.java
@@ -14,10 +14,10 @@
 
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.jdt.core.CompletionRequestor;
-import org.eclipse.jdt.core.ICompletionEngine;
-import org.eclipse.jdt.core.ICompletionEngineProvider;
 import org.eclipse.jdt.core.IJavaProject;
 import org.eclipse.jdt.core.WorkingCopyOwner;
+import org.eclipse.jdt.internal.codeassist.ICompletionEngine;
+import org.eclipse.jdt.internal.codeassist.ICompletionEngineProvider;
 import org.eclipse.jdt.internal.core.SearchableEnvironment;
 import org.eclipse.jdt.internal.javac.completion.DOMCompletionEngine;
 

diff --git a/...pse.jdt.core.javac/src/org/eclipse/jdt/internal/javac/completion/DOMCompletionEngine.java b/...pse.jdt.core.javac/src/org/eclipse/jdt/internal/javac/completion/DOMCompletionEngine.java
@@ -41,7 +41,6 @@
 import org.eclipse.jdt.core.Flags;
 import org.eclipse.jdt.core.IAnnotation;
 import org.eclipse.jdt.core.ICompilationUnit;
-import org.eclipse.jdt.core.ICompletionEngine;
 import org.eclipse.jdt.core.IField;
 import org.eclipse.jdt.core.IJavaElement;
 import org.eclipse.jdt.core.IJavaProject;
@@ -93,7 +92,6 @@
 import org.eclipse.jdt.core.dom.MethodInvocation;
 import org.eclipse.jdt.core.dom.MethodRef;
 import org.eclipse.jdt.core.dom.Modifier;
-import org.eclipse.jdt.core.dom.Modifier.ModifierKeyword;
 import org.eclipse.jdt.core.dom.ModuleDeclaration;
 import org.eclipse.jdt.core.dom.Name;
 import org.eclipse.jdt.core.dom.NameQualifiedType;
@@ -125,6 +123,7 @@
 import org.eclipse.jdt.core.dom.VariableDeclaration;
 import org.eclipse.jdt.core.dom.VariableDeclarationFragment;
 import org.eclipse.jdt.core.dom.VariableDeclarationStatement;
+import org.eclipse.jdt.core.dom.Modifier.ModifierKeyword;
 import org.eclipse.jdt.core.formatter.DefaultCodeFormatterConstants;
 import org.eclipse.jdt.core.search.IJavaSearchConstants;
 import org.eclipse.jdt.core.search.SearchEngine;
@@ -133,6 +132,7 @@
 import org.eclipse.jdt.internal.codeassist.CompletionEngine;
 import org.eclipse.jdt.internal.codeassist.DOMCodeSelector;
 import org.eclipse.jdt.internal.codeassist.ExpectedTypes;
+import org.eclipse.jdt.internal.codeassist.ICompletionEngine;
 import org.eclipse.jdt.internal.codeassist.InternalCompletionProposal;
 import org.eclipse.jdt.internal.codeassist.RelevanceConstants;
 import org.eclipse.jdt.internal.codeassist.impl.AssistOptions;
@@ -424,29 +424,40 @@ private static CompilationUnit getCompletionAST(char[] content, char[] unitName,
 	}
 
 	@Override
-	public void complete(org.eclipse.jdt.internal.compiler.env.ICompilationUnit sourceUnit, int completionPosition, int ignored, ITypeRoot root) {
+	public void complete(org.eclipse.jdt.internal.compiler.env.ICompilationUnit sourceUnit, int completionPosition, ITypeRoot root) {
 		if (this.monitor != null) {
 			this.monitor.beginTask(Messages.engine_completing, IProgressMonitor.UNKNOWN);
 		}
 		this.requestor.beginReporting();
-		
+
 		this.modelUnit = root;
 		if (modelUnit != null) {
 			try {
 				this.textContent = new String(this.modelUnit.getBuffer().getCharacters());
 			} catch (JavaModelException e) {
+				this.textContent = new String(sourceUnit.getContents());
 				ILog.get().error("unable to access buffer for completion", e); //$NON-NLS-1$
 			}
 			this.offset = completionPosition;
-			this.unit = getCompletionAST(this.modelUnit, root.getJavaProject(), this.workingCopyOwner, completionPosition);
+			if (modelUnit instanceof org.eclipse.jdt.internal.core.CompilationUnit modelCU) {
+				try {
+					this.unit = modelCU.getOrBuildAST(this.workingCopyOwner, completionPosition);
+				} catch (JavaModelException e) {
+					// do nothing
+				}
+			}
+			if (this.unit == null) {
+				this.unit = getCompletionAST(this.modelUnit, root.getJavaProject(), this.workingCopyOwner, completionPosition);
+			}
 			if (this.unit == null) {
 				return;
 			}
 		} else {
-			// uh oh
 			this.textContent = new String(sourceUnit.getContents());
 			this.offset = completionPosition;
-			this.unit = getCompletionAST(sourceUnit.getContents(), sourceUnit.getFileName(), this.javaProject, this.workingCopyOwner, completionPosition);
+			if (this.unit == null) {
+				this.unit = getCompletionAST(sourceUnit.getContents(), sourceUnit.getFileName(), this.javaProject, this.workingCopyOwner, completionPosition);
+			}
 		}
 
 

diff --git a/org.eclipse.jdt.core/codeassist/org/eclipse/jdt/internal/codeassist/CompletionEngine.java b/org.eclipse.jdt.core/codeassist/org/eclipse/jdt/internal/codeassist/CompletionEngine.java
@@ -1938,6 +1938,11 @@ private boolean complete(
 		return true;
 	}
 
+	@Override
+	public void complete(ICompilationUnit sourceUnit, int completionPosition, ITypeRoot root) {
+		complete(sourceUnit, completionPosition, 0, root);
+	}
+
 	/**
 	 * Ask the engine to compute a completion at the specified position
 	 * of the given compilation unit.
@@ -1952,7 +1957,6 @@ private boolean complete(
 	 *      a position in the source where the completion is taking place.
 	 *      This position is relative to the source provided.
 	 */
-	@Override
 	public void complete(ICompilationUnit sourceUnit, int completionPosition, int pos, ITypeRoot root) {
 
 		if(DEBUG) {

diff --git a/...g/eclipse/jdt/core/ICompletionEngine.java → ...nternal/codeassist/ICompletionEngine.java b/...g/eclipse/jdt/core/ICompletionEngine.java → ...nternal/codeassist/ICompletionEngine.java
@@ -8,8 +8,9 @@
  *
  * SPDX-License-Identifier: EPL-2.0
  *******************************************************************************/
-package org.eclipse.jdt.core;
+package org.eclipse.jdt.internal.codeassist;
 
+import org.eclipse.jdt.core.ITypeRoot;
 import org.eclipse.jdt.internal.compiler.env.ICompilationUnit;
 
 /**
@@ -21,10 +22,10 @@ public interface ICompletionEngine {
 	 * Provide completion items based on the given source unit and completion position to the configured requestor.
 	 *
 	 * @param sourceUnit the compilation unit for which completion was triggered
+	 * @param ast the AST of the compilation unit to use for completion. can be null, in which case the completion engine is expected to build it
 	 * @param completionPosition the position that completion was triggered at
-	 * @param pos should always be 0, don't set it to anything else
 	 * @param root the type root for which completion was triggered
 	 */
-	public void complete(ICompilationUnit sourceUnit, int completionPosition, int pos, ITypeRoot root);
+	public void complete(ICompilationUnit sourceUnit, int completionPosition, ITypeRoot root);
 
 }
diff --git a/...e/jdt/core/ICompletionEngineProvider.java → ...codeassist/ICompletionEngineProvider.java b/...e/jdt/core/ICompletionEngineProvider.java → ...codeassist/ICompletionEngineProvider.java
@@ -8,10 +8,13 @@
  *
  * SPDX-License-Identifier: EPL-2.0
  *******************************************************************************/
-package org.eclipse.jdt.core;
+package org.eclipse.jdt.internal.codeassist;
 
 import java.util.Map;
 import org.eclipse.core.runtime.IProgressMonitor;
+import org.eclipse.jdt.core.CompletionRequestor;
+import org.eclipse.jdt.core.IJavaProject;
+import org.eclipse.jdt.core.WorkingCopyOwner;
 import org.eclipse.jdt.internal.core.SearchableEnvironment;
 
 /**

diff --git a/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/CompilationUnit.java b/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/CompilationUnit.java
@@ -448,14 +448,10 @@ public void codeComplete(int offset, CompletionRequestor requestor, WorkingCopyO
 
 @Override
 public void codeComplete(int offset, CompletionRequestor requestor, WorkingCopyOwner workingCopyOwner, IProgressMonitor monitor) throws JavaModelException {
-	codeComplete(
-			this,
+
+	codeComplete(this,
 			isWorkingCopy() ? (org.eclipse.jdt.internal.compiler.env.ICompilationUnit) getOriginalElement() : this,
-			offset,
-			requestor,
-			workingCopyOwner,
-			this,
-			monitor);
+			offset, requestor, workingCopyOwner, this, monitor);
 }
 
 /**
@@ -477,20 +473,27 @@ public IJavaElement[] codeSelect(int offset, int length, WorkingCopyOwner workin
 	}
 }
 
-public org.eclipse.jdt.core.dom.CompilationUnit getOrBuildAST(WorkingCopyOwner workingCopyOwner) throws JavaModelException {
+public org.eclipse.jdt.core.dom.CompilationUnit getOrBuildAST(WorkingCopyOwner workingCopyOwner, int focalPosition) throws JavaModelException {
 	if (this.ast != null) {
 		return this.ast;
 	}
 	Map<String, String> options = getOptions(true);
 	ASTParser parser = ASTParser.newParser(new AST(options).apiLevel()); // go through AST constructor to convert options to apiLevel
+	// but we should probably instead just use the latest Java version
+	// supported by the compiler
 	parser.setWorkingCopyOwner(workingCopyOwner);
 	parser.setSource(this);
 	// greedily enable everything assuming the AST will be used extensively for edition
 	parser.setResolveBindings(true);
 	parser.setStatementsRecovery(true);
 	parser.setBindingsRecovery(true);
 	parser.setCompilerOptions(options);
+	parser.setFocalPosition(focalPosition);
 	if (parser.createAST(null) instanceof org.eclipse.jdt.core.dom.CompilationUnit newAST) {
+		if (focalPosition >= 0) {
+			// do not store
+			return newAST;
+		}
 		this.ast = newAST;
 	}
 	return this.ast;

diff --git a/...lipse.jdt.core/model/org/eclipse/jdt/internal/core/CompletionEngineProviderDiscovery.java b/...lipse.jdt.core/model/org/eclipse/jdt/internal/core/CompletionEngineProviderDiscovery.java
@@ -17,9 +17,9 @@
 import org.eclipse.core.runtime.IExtensionPoint;
 import org.eclipse.core.runtime.ILog;
 import org.eclipse.core.runtime.Platform;
-import org.eclipse.jdt.core.ICompletionEngineProvider;
 import org.eclipse.jdt.core.JavaCore;
 import org.eclipse.jdt.internal.codeassist.CompletionEngine;
+import org.eclipse.jdt.internal.codeassist.ICompletionEngineProvider;
 
 class CompletionEngineProviderDiscovery {
 	private static final String SELECTED_SYSPROP = "ICompletionEngineProvider"; //$NON-NLS-1$

diff --git a/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/Openable.java b/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/Openable.java
@@ -24,6 +24,8 @@
 import org.eclipse.core.runtime.PerformanceStats;
 import org.eclipse.jdt.core.*;
 import org.eclipse.jdt.internal.codeassist.CompletionEngine;
+import org.eclipse.jdt.internal.codeassist.ICompletionEngine;
+import org.eclipse.jdt.internal.codeassist.ICompletionEngineProvider;
 import org.eclipse.jdt.internal.codeassist.SelectionEngine;
 import org.eclipse.jdt.internal.compiler.env.IElementInfo;
 import org.eclipse.jdt.internal.core.util.Util;
@@ -134,7 +136,7 @@ protected void codeComplete(
 	// code complete
 	ICompletionEngineProvider completionEngineProvider = CompletionEngineProviderDiscovery.getInstance();
 	ICompletionEngine completionEngine = completionEngineProvider.getCompletionEngine(environment, requestor, project.getOptions(true), project, owner, monitor);
-	completionEngine.complete(cu, position, 0, typeRoot);
+	completionEngine.complete(cu, position, typeRoot);
 
 	if(performanceStats != null) {
 		performanceStats.endRun();