🐛 Resolves the referenced element before parsing colors (#6782)

AlexV525 · web-flow · commit 16749f9cbf49 · 2023-08-16T11:25:03.000-07:00
Fixes #5436 #6777. The PR does: - Resolves PSI elements if they are `VAR_INIT` or `FUNCTION_BODY` before parsing, which can always lead to a correct definition eventually. - Improve `const Color.from*` constructors handling. - Only handle the last child of an element's children to avoid too many requests when gathering line markers, thus `Colors.blue.shade700` will only resolve color on `shade700` instead of `Colors`, `blue`, and `shade700`. ## Pre-launch Checklist - [x] I read the [Contributor Guide] and followed the process outlined there for submitting PRs. - [x] I read the [Tree Hygiene] wiki page, which explains my responsibilities. - [x] I read the [Flutter Style Guide] _recently_, and have followed its advice. - [x] I signed the [CLA]. - [x] I listed at least one issue that this PR fixes in the description above. - [x] I updated/added relevant documentation (doc comments with `///`). - [x] I added new tests to check the change I am making, or this PR is [test-exempt]. - [x] All existing and new tests are passing.  [Contributor Guide]: https://github.com/flutter/flutter/wiki/Tree-hygiene#overview [Tree Hygiene]: https://github.com/flutter/flutter/wiki/Tree-hygiene [test-exempt]: https://github.com/flutter/flutter/wiki/Tree-hygiene#tests [Flutter Style Guide]: https://github.com/flutter/flutter/wiki/Style-guide-for-Flutter-repo [CLA]: https://cla.developers.google.com/ [flutter/tests]: https://github.com/flutter/tests [breaking change policy]: https://github.com/flutter/flutter/wiki/Tree-hygiene#handling-breaking-changes [Discord]: https://github.com/flutter/flutter/wiki/Chat
diff --git a/flutter-idea/src/io/flutter/editor/FlutterColorProvider.java b/flutter-idea/src/io/flutter/editor/FlutterColorProvider.java
@@ -14,10 +14,7 @@
 import com.intellij.psi.impl.source.tree.AstBufferUtil;
 import com.jetbrains.lang.dart.DartLanguage;
 import com.jetbrains.lang.dart.DartTokenTypes;
-import com.jetbrains.lang.dart.psi.DartArgumentList;
-import com.jetbrains.lang.dart.psi.DartArguments;
-import com.jetbrains.lang.dart.psi.DartExpression;
-import com.jetbrains.lang.dart.psi.DartLiteralExpression;
+import com.jetbrains.lang.dart.psi.*;
 import io.flutter.FlutterBundle;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -38,7 +35,7 @@ public Color getColorFrom(@NotNull PsiElement element) {
     if (element.getNode().getElementType() != DartTokenTypes.IDENTIFIER) return null;
 
     final String name = element.getText();
-    if (!(name.equals("Colors") || name.equals("CupertinoColors") || name.equals("Color"))) return null;
+    if (name == null) return null;
 
     final PsiElement refExpr = topmostReferenceExpression(element);
     if (refExpr == null) return null;
@@ -47,21 +44,66 @@ public Color getColorFrom(@NotNull PsiElement element) {
 
     if (parent.getNode().getElementType() == DartTokenTypes.ARRAY_ACCESS_EXPRESSION) {
       // Colors.blue[200]
+      if (name.equals(refExpr.getFirstChild().getText()) && refExpr.getChildren().length > 1) {
+        // Avoid duplicate resolves.
+        return null;
+      }
       final String code = AstBufferUtil.getTextSkippingWhitespaceComments(parent.getNode());
-      return parseColorText(code.substring(code.indexOf(name) + name.length() + 1), name);
+      return parseColorText(code.substring(code.indexOf(name)), name);
     }
     else if (parent.getNode().getElementType() == DartTokenTypes.CALL_EXPRESSION) {
       // foo(Color.fromRGBO(0, 255, 0, 0.5))
+      if (name.matches("fromARGB") || name.matches("fromRGBO")) {
+        // Avoid duplicate resolves.
+        return null;
+      }
+      if (parent.getLastChild() instanceof DartArguments && !name.matches("(Cupertino)?Color")) {
+        // Avoid duplicate resolves.
+        final DartExpression colorExpression = ((DartArguments)parent.getLastChild()).getArgumentList().getExpressionList().get(0);
+        final Color color = parseColorElements(colorExpression, colorExpression.getFirstChild());
+        if (color != null) return null;
+      }
+      // Color.fromRGBO(0, 255, 0, 0.5)
       return parseColorElements(parent, refExpr);
     }
     else if (parent.getNode().getElementType() == DartTokenTypes.SIMPLE_TYPE) {
       // const Color.fromARGB(100, 255, 0, 0)
+      if (name.matches("fromARGB") || name.matches("fromRGBO")) {
+        // Avoid duplicate resolves.
+        return null;
+      }
       // parent.getParent().getParent() is a new expr
       parent = getNewExprFromType(parent);
       if (parent == null) return null;
       return parseColorElements(parent, refExpr);
     }
     else {
+      if (parent.getNode().getElementType() == DartTokenTypes.VAR_INIT ||
+          parent.getNode().getElementType() == DartTokenTypes.FUNCTION_BODY) {
+        if (name.equals(refExpr.getFirstChild().getText()) && refExpr.getChildren().length > 1) {
+          // Avoid duplicate resolves.
+          return null;
+        }
+        final PsiElement reference = resolveReferencedElement(refExpr);
+        if (reference != null && reference.getLastChild() != null) {
+          Color tryParseColor = null;
+          if (reference instanceof DartCallExpression) {
+            final DartExpression expression = ((DartCallExpression)reference).getExpression();
+            if (expression != null && expression.getLastChild() instanceof DartReferenceExpression) {
+              tryParseColor = parseColorElements(reference, expression);
+              if (tryParseColor != null) return tryParseColor;
+            }
+          }
+          final PsiElement lastChild = reference.getLastChild();
+          if (lastChild instanceof DartArguments && reference.getParent() != null) {
+            tryParseColor = parseColorElements(reference, reference.getParent());
+          }
+          else {
+            tryParseColor = parseColorElements(reference, reference.getLastChild());
+          }
+          if (tryParseColor != null) return tryParseColor;
+        }
+      }
       // name.equals(refExpr.getFirstChild().getText()) -> Colors.blue
       final PsiElement idNode = refExpr.getFirstChild();
       if (idNode == null) return null;
@@ -75,13 +117,46 @@ else if (parent.getNode().getElementType() == DartTokenTypes.SIMPLE_TYPE) {
       final PsiElement child = refExpr.getLastChild();
       if (child == null) return null;
       if (child.getText().startsWith("shade")) {
-        final String code = AstBufferUtil.getTextSkippingWhitespaceComments(refExpr.getNode());
-        return parseColorText(code.substring(code.indexOf(name) + name.length() + 1), name);
+        if (idNode.getText().contains(name)) return null; // Avoid duplicate resolves.
+        String code = AstBufferUtil.getTextSkippingWhitespaceComments(refExpr.getNode());
+        code = code.replaceFirst("(Cupertino)?Colors\\.", "");
+        return parseColorText(code, name);
       }
     }
     return null;
   }
 
+  @Nullable
+  private PsiElement resolveReferencedElement(@NotNull PsiElement element) {
+    if (element instanceof DartCallExpression && element.getFirstChild().getText().equals("Color")) {
+      return element;
+    }
+    final PsiElement symbol = element.getLastChild();
+    final PsiElement result;
+    if (symbol instanceof DartReference) {
+      result = ((DartReference)symbol).resolve();
+    }
+    else if (element instanceof DartReference) {
+      result = ((DartReference)element).resolve();
+    }
+    else {
+      return null;
+    }
+    if (!(result instanceof DartComponentName) || result.getParent() == null) return null;
+    final PsiElement declaration = result.getParent().getParent();
+    if (declaration instanceof DartClassMembers) return declaration;
+    if (!(declaration instanceof DartVarDeclarationList)) return null;
+    final PsiElement lastChild = declaration.getLastChild();
+    if (!(lastChild instanceof DartVarInit)) return null;
+
+    final PsiElement effectiveElement = lastChild.getLastChild();
+    // Recursively determine reference if the initialization is still a `DartReference`.
+    if (effectiveElement instanceof DartReference && !(effectiveElement instanceof DartCallExpression)) {
+      return resolveReferencedElement(effectiveElement);
+    }
+    return effectiveElement;
+  }
+
   @Nullable
   private Color parseColorElements(@NotNull PsiElement parent, @NotNull PsiElement refExpr) {
     final PsiElement selectorNode = refExpr.getLastChild();
@@ -91,7 +166,7 @@ private Color parseColorElements(@NotNull PsiElement parent, @NotNull PsiElement
     final boolean isFromRGBO = "fromRGBO".equals(selector);
     if (isFromARGB || isFromRGBO) {
       String code = AstBufferUtil.getTextSkippingWhitespaceComments(parent.getNode());
-      if (code.startsWith("constColor(")) {
+      if (code.startsWith("constColor(") || code.startsWith("constColor.")) {
         code = code.substring(5);
       }
       return ExpressionParsingUtils.parseColorComponents(code.substring(code.indexOf(selector)), selector + "(", isFromARGB);
diff --git a/flutter-idea/testSrc/unit/io/flutter/editor/FlutterColorProviderTest.java b/flutter-idea/testSrc/unit/io/flutter/editor/FlutterColorProviderTest.java
@@ -122,7 +122,7 @@ public void locatesRGBOColor() throws Exception {
   @Test
   public void locatesColorShadeReference() throws Exception {
     run(() -> {
-      final PsiElement testIdentifier = setUpDartElement("main() { Colors.blue.shade700; }", "Colors", LeafPsiElement.class);
+      final PsiElement testIdentifier = setUpDartElement("main() { Colors.blue.shade700; }", "shade700", LeafPsiElement.class);
       final Color color = new FlutterColorProvider().getColorFrom(testIdentifier);
       assertNotNull(color);
       final DartReferenceExpression element = DartSyntax.findEnclosingReferenceExpression(testIdentifier);
@@ -133,7 +133,7 @@ public void locatesColorShadeReference() throws Exception {
   @Test
   public void locatesColorArrayReference() throws Exception {
     run(() -> {
-      final PsiElement testIdentifier = setUpDartElement("main() { Colors.blue[200]]; }", "Colors", LeafPsiElement.class);
+      final PsiElement testIdentifier = setUpDartElement("main() { Colors.blue[200]; }", "blue", LeafPsiElement.class);
       final Color color = new FlutterColorProvider().getColorFrom(testIdentifier);
       assertNotNull(color);
       final DartReferenceExpression element = DartSyntax.findEnclosingReferenceExpression(testIdentifier);
@@ -155,7 +155,7 @@ public void locatesCuppertinoColorReference() throws Exception {
   @Test
   public void locatesColorReferenceWithComment() throws Exception {
     run(() -> {
-      final PsiElement testIdentifier = setUpDartElement("main() { Colors . blue . /* darkish */ shade700; }", "Colors", LeafPsiElement.class);
+      final PsiElement testIdentifier = setUpDartElement("main() { Colors . blue . /* darkish */ shade700; }", "shade700", LeafPsiElement.class);
       final Color color = new FlutterColorProvider().getColorFrom(testIdentifier);
       assertNotNull(color);
       final DartReferenceExpression element = DartSyntax.findEnclosingReferenceExpression(testIdentifier);
