#452: introduce method separators

src/META-INF/plugin.xml

@@ -115,6 +115,7 @@
 
         <codeInsight.lineMarkerProvider language="Erlang" implementationClass="org.intellij.erlang.marker.ErlangRecursiveCallLineMarkerProvider"/>
         <codeInsight.lineMarkerProvider language="Erlang" implementationClass="org.intellij.erlang.marker.ErlangBehaviourMarkerProvider"/>
+        <codeInsight.lineMarkerProvider language="Erlang" implementationClass="org.intellij.erlang.marker.ErlangMethodSeparatorProvider"/>
 
         <codeInsight.parameterInfo language="Erlang" implementationClass="org.intellij.erlang.ErlangParameterInfoHandler"/>
         <codeInsight.gotoSuper language="Erlang" implementationClass="org.intellij.erlang.navigation.ErlangGotoSuperHandler"/>

src/org/intellij/erlang/marker/ErlangMethodSeparatorProvider.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright 2012-2014 Sergey Ignatov
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.intellij.erlang.marker;
+
+import com.intellij.codeInsight.daemon.DaemonCodeAnalyzerSettings;
+import com.intellij.codeInsight.daemon.LineMarkerInfo;
+import com.intellij.codeInsight.daemon.LineMarkerProvider;
+import com.intellij.codeInsight.daemon.impl.LineMarkersPass;
+import com.intellij.openapi.editor.colors.EditorColorsManager;
+import com.intellij.psi.PsiComment;
+import com.intellij.psi.PsiElement;
+import com.intellij.psi.PsiReference;
+import com.intellij.psi.PsiWhiteSpace;
+import com.intellij.psi.util.PsiTreeUtil;
+import org.intellij.erlang.psi.*;
+import org.intellij.erlang.psi.impl.ErlangPsiImplUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Collection;
+import java.util.List;
+
+public class ErlangMethodSeparatorProvider implements LineMarkerProvider {
+  private final DaemonCodeAnalyzerSettings myDaemonSettings;
+  private final EditorColorsManager myColorsManager;
+
+  public ErlangMethodSeparatorProvider(DaemonCodeAnalyzerSettings daemonSettings, EditorColorsManager colorsManager) {
+    myDaemonSettings = daemonSettings;
+    myColorsManager = colorsManager;
+  }
+
+  @Nullable
+  @Override
+  public LineMarkerInfo getLineMarkerInfo(@NotNull PsiElement function) {
+    if (myDaemonSettings.SHOW_METHOD_SEPARATORS && function instanceof ErlangFunction) {
+      PsiElement anchor = findAnchorElementForMethodSeparator((ErlangFunction) function);
+      return LineMarkersPass.createMethodSeparatorLineMarker(anchor, myColorsManager);
+    }
+    return null;
+  }
+
+  @Override
+  public void collectSlowLineMarkers(@NotNull List<PsiElement> elements, @NotNull Collection<LineMarkerInfo> result) {
+  }
+
+  private static PsiElement findAnchorElementForMethodSeparator(ErlangFunction function) {
+    ErlangAttribute specAttribute = getSpecAttributeForFunction(function);
+    PsiElement leftmostPossibleAnchor = function;
+    PsiElement leftmostElement = function;
+    while ((leftmostElement = leftmostElement.getPrevSibling()) != null) {
+      if (leftmostElement instanceof PsiComment || leftmostElement == specAttribute) {
+        leftmostPossibleAnchor = leftmostElement;
+      }
+      else if (!(leftmostElement instanceof PsiWhiteSpace)) break;
+    }
+    return leftmostPossibleAnchor;
+  }
+
+  @Nullable
+  private static ErlangAttribute getSpecAttributeForFunction(ErlangFunction function) {
+    ErlangSpecification spec = ErlangPsiImplUtil.getSpecification(function);
+    ErlangFunTypeSigs signature = ErlangPsiImplUtil.getSignature(spec);
+    ErlangSpecFun specFun = signature != null ? signature.getSpecFun() : null;
+    PsiReference reference = specFun != null ? specFun.getReference() : null;
+    boolean isSpecForPassedFunction = reference != null && reference.isReferenceTo(function);
+    return isSpecForPassedFunction ? PsiTreeUtil.getParentOfType(spec, ErlangAttribute.class) : null;
+  }
+}

testData/marker/methodSeparators/comment.erl

@@ -0,0 +1,3 @@
+% comment
+foo() ->
+  ok.

testData/marker/methodSeparators/commentAndSpec.erl

@@ -0,0 +1,4 @@
+% comment
+-spec foo() -> ok.
+foo() ->
+  ok.

testData/marker/methodSeparators/commentSpecAndComment.erl

@@ -0,0 +1,5 @@
+% comment
+-spec foo() -> ok.
+% comment
+foo() ->
+  ok.

testData/marker/methodSeparators/function.erl

@@ -0,0 +1,2 @@
+foo() ->
+  ok.

testData/marker/methodSeparators/spec.erl

@@ -0,0 +1,3 @@
+-spec foo() -> ok.
+foo() ->
+  ok.

testData/marker/methodSeparators/specAndComment.erl

@@ -0,0 +1,4 @@
+-spec foo() -> ok.
+% comment
+foo() ->
+  ok.

testData/marker/methodSeparators/specOfOtherFunction.erl

@@ -0,0 +1,3 @@
+-spec bar() -> ok.
+foo() ->
+  ok.

testData/marker/methodSeparators/twoFunctions.erl

@@ -0,0 +1,5 @@
+foo() ->
+  ok.
+
+bar() ->
+  ok.

tests/org/intellij/erlang/marker/ErlangMethodSeparatorProviderTest.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2012-2014 Sergey Ignatov
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.intellij.erlang.marker;
+
+import com.intellij.codeInsight.daemon.DaemonCodeAnalyzerSettings;
+import com.intellij.codeInsight.daemon.LineMarkerInfo;
+import com.intellij.codeInsight.daemon.impl.DaemonCodeAnalyzerImpl;
+import org.intellij.erlang.utils.ErlangLightPlatformCodeInsightFixtureTestCase;
+
+import java.util.List;
+
+public class ErlangMethodSeparatorProviderTest extends ErlangLightPlatformCodeInsightFixtureTestCase {
+  @Override
+  protected void setUp() throws Exception {
+    super.setUp();
+    setShowMethodSeparatorsEnabled(true);
+  }
+
+  @Override
+  protected void tearDown() throws Exception {
+    super.tearDown();
+    setShowMethodSeparatorsEnabled(false);
+  }
+
+  @Override
+  protected String getTestDataPath() {
+    return "testData/marker/methodSeparators/";
+  }
+
+  @Override
+  protected boolean isWriteActionRequired() {
+    return false;
+  }
+
+  private static void setShowMethodSeparatorsEnabled(boolean b) {
+    DaemonCodeAnalyzerSettings settings = DaemonCodeAnalyzerSettings.getInstance();
+    settings.SHOW_METHOD_SEPARATORS = b;
+  }
+
+  protected void doTest(Integer ... expectedLineMarkers) {
+    myFixture.configureByFile(getTestName(true) + ".erl");
+    myFixture.doHighlighting();
+    assertSameElements(getMarkedLineNumbers(), expectedLineMarkers);
+  }
+
+  private Integer[] getMarkedLineNumbers() {
+    List<LineMarkerInfo> lineMarkers = DaemonCodeAnalyzerImpl.getLineMarkers(myFixture.getEditor().getDocument(), myFixture.getProject());
+    assertNotNull(lineMarkers);
+    Integer[] markedLineNumbers = new Integer[lineMarkers.size()];
+    for (int i = 0; i < lineMarkers.size(); i++) {
+      markedLineNumbers[i] = myFixture.getEditor().getDocument().getLineNumber(lineMarkers.get(i).startOffset);
+    }
+    return markedLineNumbers;
+  }
+
+  public void testFunction()              throws Exception { doTest(0); }
+  public void testTwoFunctions()          throws Exception { doTest(0, 3); }
+  public void testSpec()                  throws Exception { doTest(0); }
+  public void testComment()               throws Exception { doTest(0); }
+  public void testSpecAndComment()        throws Exception { doTest(0); }
+  public void testCommentAndSpec()        throws Exception { doTest(0); }
+  public void testCommentSpecAndComment() throws Exception { doTest(0); }
+  public void testSpecOfOtherFunction()   throws Exception { doTest(1); }
+}