From 07e1c5a55c893ecc6fdad5be73096d6d6e079870 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Simon=20Lars=C3=A9n?= <slarse@kth.se>
Date: Wed, 4 Mar 2020 10:57:32 +0100
Subject: [PATCH] [feat] Compare with gumtree-spoon, ignoring comments, fix #45

---
 src/main/java/se/kth/spork/cli/Cli.java       | 28 +++++++++++++------
 src/main/java/se/kth/spork/spoon/Compare.java | 14 ++++++++++
 src/main/java/se/kth/spork/spoon/Parser.java  | 17 +++++++++++
 3 files changed, 51 insertions(+), 8 deletions(-)

diff --git a/src/main/java/se/kth/spork/cli/Cli.java b/src/main/java/se/kth/spork/cli/Cli.java
index 5f92d5c5..05cc5f63 100644
--- a/src/main/java/se/kth/spork/cli/Cli.java
+++ b/src/main/java/se/kth/spork/cli/Cli.java
@@ -1,5 +1,7 @@
 package se.kth.spork.cli;
 
+import gumtree.spoon.AstComparator;
+import gumtree.spoon.diff.Diff;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import picocli.CommandLine;
@@ -69,7 +71,7 @@ public Integer call() {
     }
 
     @CommandLine.Command(name = "compare", mixinStandardHelpOptions = true,
-            description = "Compare the ASTs of two Java files, disregarding the order of unordered elements")
+            description = "Compare the ASTs of two Java files, disregarding comments and the order of unordered elements")
     private static class CompareCommand implements Callable<Integer> {
         @CommandLine.Parameters(index = "0", paramLabel = "LEFT", description = "Path to a Java file")
         File left;
@@ -79,16 +81,26 @@ private static class CompareCommand implements Callable<Integer> {
 
         @Override
         public Integer call() {
-            CtModule leftModule = Parser.parse(left.toPath());
-            CtModule rightModule = Parser.parse(right.toPath());
+            CtModule leftModule = Parser.parseWithoutComments(left.toPath());
+            CtModule rightModule = Parser.parseWithoutComments(right.toPath());
+
+            Compare.sortUnorderedElements(leftModule);
+            Compare.sortUnorderedElements(rightModule);
 
-            if (Compare.compare(leftModule, rightModule)) {
-                LOGGER.info("The ASTs are equal");
-                return 0;
+            Object leftImports = leftModule.getMetadata(Parser.IMPORT_STATEMENTS);
+            Object rightImports = rightModule.getMetadata(Parser.IMPORT_STATEMENTS);
+
+            Diff diff = new AstComparator().compare(leftModule, rightModule);
+            System.out.println(diff);
+
+            boolean importsEqual = leftImports.equals(rightImports);
+            if (!importsEqual) {
+                LOGGER.warn("Import statements differ");
+                LOGGER.info("Left: " + leftImports);
+                LOGGER.info("Right: " + rightImports);
             }
 
-            LOGGER.info("The ASTs differ");
-            return 1;
+            return diff.getRootOperations().isEmpty() && importsEqual ? 0 : 1;
         }
     }
 
diff --git a/src/main/java/se/kth/spork/spoon/Compare.java b/src/main/java/se/kth/spork/spoon/Compare.java
index acb382ab..d3659417 100644
--- a/src/main/java/se/kth/spork/spoon/Compare.java
+++ b/src/main/java/se/kth/spork/spoon/Compare.java
@@ -40,6 +40,20 @@ public static boolean compare(CtModule left, CtModule right) {
                 compare(left.getRootPackage().clone(), right.getRootPackage().clone());
     }
 
+    /**
+     * Sort the unordered elements of the provided module.
+     *
+     * @param mod A Spoon unnamed module.
+     */
+    public static void sortUnorderedElements(CtModule mod) {
+        sortUnorderedElements(mod.getRootPackage());
+    }
+
+    private static void sortUnorderedElements(CtPackage pkg) {
+        pkg.getTypes().forEach(Compare::sortTypeMembers);
+        pkg.getPackages().forEach(Compare::sortUnorderedElements);
+    }
+
     /**
      * Compare the left package with the right package, without regard to the order of unordered type
      * members.
diff --git a/src/main/java/se/kth/spork/spoon/Parser.java b/src/main/java/se/kth/spork/spoon/Parser.java
index 7be7beeb..e144feae 100644
--- a/src/main/java/se/kth/spork/spoon/Parser.java
+++ b/src/main/java/se/kth/spork/spoon/Parser.java
@@ -44,6 +44,23 @@ public static CtModule parse(String javaFileContents) {
         return parse(launcher -> launcher.addInputResource(new VirtualFile(javaFileContents)));
     }
 
+    /**
+     * Parse a Java file to a Spoon tree. Any import statements in the file are attached to the returned module's
+     * metadata with the {@link Parser#IMPORT_STATEMENTS} key. The imports are sorted in ascending lexicographical
+     * order.
+     *
+     * Comments are ignored
+     *
+     * @param javaFile Path to a Java file.
+     * @return The root module of the Spoon tree.
+     */
+    public static CtModule parseWithoutComments(Path javaFile) {
+        return parse(launcher -> {
+            launcher.getEnvironment().setCommentEnabled(false);
+            launcher.addInputResource(new VirtualFile(read(javaFile)));
+        });
+    }
+
     private static CtModule parse(Consumer<Launcher> addResource) {
         Launcher launcher = new Launcher();
         launcher.getEnvironment().setPrettyPrinterCreator(