[core] Add operations to manipulate a document

pmd-core/src/main/java/net/sourceforge/pmd/util/document/DocumentFile.java

@@ -7,14 +7,12 @@
 import java.io.BufferedReader;
 import java.io.Closeable;
 import java.io.File;
-import java.io.FileReader;
-import java.io.FileWriter;
 import java.io.IOException;
 import java.io.Writer;
+import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
-import java.nio.file.StandardCopyOption;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Scanner;
@@ -36,26 +34,42 @@ public class DocumentFile implements Document, Closeable {
     private final BufferedReader reader;
     private int currentPosition = 0;
 
-    private final Path temporaryPath = Files.createTempFile("pmd-", null);
-    private final Writer writer = new FileWriter(temporaryPath.toFile());
+    private final Path temporaryPath = Files.createTempFile("pmd-", ".tmp");
+    private final Writer writer = Files.newBufferedWriter(temporaryPath, StandardCharsets.UTF_8);
 
     public DocumentFile(final File file) throws IOException {
-        reader = new BufferedReader(new FileReader(file));
+        reader = Files.newBufferedReader(file.toPath(), StandardCharsets.UTF_8);
         this.filePath = file.getAbsolutePath();
         mapLinesToOffsets();
     }
 
     private void mapLinesToOffsets() throws IOException {
-        try (Scanner scanner = new Scanner(filePath)) {
+        try (Scanner scanner = new Scanner(Paths.get(filePath))) {
             int currentGlobalOffset = 0;
 
             while (scanner.hasNextLine()) {
                 lineToOffset.add(currentGlobalOffset);
-                currentGlobalOffset += scanner.nextLine().length();
+                currentGlobalOffset += getLineLengthWithLineSeparator(scanner);
             }
         }
     }
 
+    /**
+     * Sums the line length without the line separation and the characters which matched the line separation pattern
+     * @param scanner the scanner from which to read the line's length
+     * @return the length of the line with the line separator.
+     */
+    private int getLineLengthWithLineSeparator(final Scanner scanner) {
+        int lineLength = scanner.nextLine().length();
+        final String lineSeparationMatch = scanner.match().group(1);
+
+        if (lineSeparationMatch != null) {
+            lineLength += lineSeparationMatch.length();
+        }
+
+        return lineLength;
+    }
+
     @Override
     public void insert(int beginLine, int beginColumn, final String textToInsert) {
         try {
@@ -135,7 +149,10 @@ public void close() throws IOException {
         }
         reader.close();
         writer.close();
-        Files.copy(temporaryPath, Paths.get(filePath), StandardCopyOption.REPLACE_EXISTING);
+
+        if (!temporaryPath.toFile().renameTo(new File(filePath))) {
+            throw new IOException("Fixed file could not be renamed. Original path = " + filePath);
+        }
         temporaryPath.toFile().delete();
     }
 
@@ -146,4 +163,8 @@ private void writeUntilEOF() throws IOException {
             writer.write(line);
         }
     }
+
+    public List<Integer> getLineToOffset() {
+        return lineToOffset;
+    }
 }

pmd-core/src/main/java/net/sourceforge/pmd/util/document/DocumentOperationsApplierForNonOverlappingRegions.java

@@ -12,15 +12,15 @@
 
 public class DocumentOperationsApplierForNonOverlappingRegions {
 
+    private static final Comparator<DocumentOperation> COMPARATOR = new DocumentOperationNonOverlappingRegionsComparator();
+
     private final Document document;
     private final List<DocumentOperation> operations;
-    private final Comparator<DocumentOperation> comparator;
 
     private boolean applied;
 
     public DocumentOperationsApplierForNonOverlappingRegions(final Document document) {
         this.document = Objects.requireNonNull(document);
-        comparator = new DocumentOperationNonOverlappingRegionsComparator();
         operations = new ArrayList<>();
         applied = false;
     }
@@ -39,7 +39,7 @@ private void assertOperationsHaveNotBeenApplied() {
     }
 
     private int getIndexForDocumentOperation(final DocumentOperation documentOperation) {
-        int potentialIndex = Collections.binarySearch(operations, documentOperation, comparator);
+        int potentialIndex = Collections.binarySearch(operations, documentOperation, COMPARATOR);
 
         if (potentialIndex < 0) {
             return ~potentialIndex;
@@ -53,7 +53,7 @@ private int getIndexForDocumentOperation(final DocumentOperation documentOperati
     }
 
     private boolean areSiblingsEqual(final int index) {
-        return comparator.compare(operations.get(index), operations.get(index + 1)) == 0;
+        return COMPARATOR.compare(operations.get(index), operations.get(index + 1)) == 0;
     }
 
     public void apply() {
@@ -65,15 +65,15 @@ public void apply() {
         }
     }
 
-    private class DocumentOperationNonOverlappingRegionsComparator implements Comparator<DocumentOperation> {
+    private static class DocumentOperationNonOverlappingRegionsComparator implements Comparator<DocumentOperation> {
 
         @Override
         public int compare(final DocumentOperation o1, final DocumentOperation o2) {
             final RegionByLine r1 = Objects.requireNonNull(o1).getRegionByLine();
             final RegionByLine r2 = Objects.requireNonNull(o2).getRegionByLine();
 
             final int comparison;
-            if (areInsertOperations(r1, r2)) {
+            if (areInsertOperationsAtTheSameOffset(r1, r2)) {
                 comparison = 0;
             } else if (doesFirstRegionEndBeforeSecondRegionBegins(r1, r2)) {
                 comparison = -1;
@@ -85,7 +85,7 @@ public int compare(final DocumentOperation o1, final DocumentOperation o2) {
             return comparison;
         }
 
-        private boolean areInsertOperations(final RegionByLine r1, final RegionByLine r2) {
+        private boolean areInsertOperationsAtTheSameOffset(final RegionByLine r1, final RegionByLine r2) {
             return r1.getBeginLine() == r2.getBeginLine() && r1.getBeginColumn() == r2.getBeginColumn()
                     && r1.getBeginLine() == r1.getEndLine() && r1.getBeginColumn() == r1.getEndColumn();
         }

pmd-core/src/test/java/net/sourceforge/pmd/util/document/DocumentFileTest.java

@@ -6,22 +6,21 @@
 
 import static org.junit.Assert.assertEquals;
 
+import java.io.BufferedWriter;
 import java.io.File;
 import java.io.FileInputStream;
-import java.io.FileWriter;
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.List;
 
-import org.junit.After;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.TemporaryFolder;
 
-
-
-
-
 public class DocumentFileTest {
 
     private static final String FILE_PATH = "psvm.java";
@@ -35,11 +34,6 @@ public void setUpTemporaryFiles() throws IOException {
         temporaryFile = temporaryFolder.newFile(FILE_PATH);
     }
 
-    @After
-    public void deleteTemporaryFiles() {
-        temporaryFile.delete();
-    }
-
     @Test
     public void insertAtStartOfTheFileShouldSucceed() throws IOException {
         writeContentToTemporaryFile("static void main(String[] args) {}");
@@ -218,8 +212,59 @@ public void insertDeleteAndReplaceVariousTokensShouldSucceed() throws IOExceptio
         }
     }
 
+    @Test
+    public void lineToOffsetMappingWithLineFeedShouldSucceed() throws IOException {
+        final String code = "public static int main(String[] args) {" + '\n'
+                + "int var;" + '\n'
+                + "}";
+        writeContentToTemporaryFile(code);
+
+        final List<Integer> expectedLineToOffset = new ArrayList<>();
+        expectedLineToOffset.add(0);
+        expectedLineToOffset.add(40);
+        expectedLineToOffset.add(49);
+
+        try (DocumentFile documentFile = new DocumentFile(temporaryFile)) {
+            assertEquals(expectedLineToOffset, documentFile.getLineToOffset());
+        }
+    }
+
+    @Test
+    public void lineToOffsetMappingWithCarriageReturnFeedLineFeedShouldSucceed() throws IOException {
+        final String code = "public static int main(String[] args) {" + "\r\n"
+                + "int var;" + "\r\n"
+                + "}";
+        writeContentToTemporaryFile(code);
+
+        final List<Integer> expectedLineToOffset = new ArrayList<>();
+        expectedLineToOffset.add(0);
+        expectedLineToOffset.add(41);
+        expectedLineToOffset.add(51);
+
+        try (DocumentFile documentFile = new DocumentFile(temporaryFile)) {
+            assertEquals(expectedLineToOffset, documentFile.getLineToOffset());
+        }
+    }
+
+    @Test
+    public void lineToOffsetMappingWithMixedLineSeparatorsShouldSucceed() throws IOException {
+        final String code = "public static int main(String[] args) {" + "\r\n"
+                + "int var;" + "\n"
+                + "}";
+        writeContentToTemporaryFile(code);
+
+        final List<Integer> expectedLineToOffset = new ArrayList<>();
+        expectedLineToOffset.add(0);
+        expectedLineToOffset.add(41);
+        expectedLineToOffset.add(50);
+
+        try (DocumentFile documentFile = new DocumentFile(temporaryFile)) {
+            assertEquals(expectedLineToOffset, documentFile.getLineToOffset());
+        }
+    }
+
     private void writeContentToTemporaryFile(final String content) throws IOException {
-        try (FileWriter writer = new FileWriter(temporaryFile)) {
+        try (BufferedWriter writer = Files.newBufferedWriter(temporaryFile.toPath(), StandardCharsets.UTF_8)) {
             writer.write(content);
         }
     }

pmd-core/src/test/java/net/sourceforge/pmd/util/document/DocumentOperationsApplierForNonOverlappingRegionsWithDocumentFileTest.java

@@ -15,7 +15,6 @@
 import java.util.LinkedList;
 import java.util.List;
 
-import org.junit.After;
 import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
@@ -36,11 +35,6 @@ public void setUpTemporaryFiles() throws IOException {
         temporaryFile = temporaryFolder.newFile(FILE_PATH);
     }
 
-    @After
-    public void deleteTemporaryFiles() {
-        temporaryFile.delete();
-    }
-
     @Test
     public void insertAtStartOfTheDocumentShouldSucceed() throws IOException {
         writeContentToTemporaryFile("static void main(String[] args) {}");