8285452: Add a new test library API to replace a file content using F…

…ileUtils.java

Backport-of: 0462d5a25258458ec7f40d76b9d910ee529f3647

test/lib-test/jdk/test/lib/FileUtilsTest.java

@@ -0,0 +1,124 @@
+/*
+ * Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/* @test
+ * @bug 8285452
+ * @summary Unit Test for a common Test API in jdk.test.lib.util.FileUtils
+ * @library .. /test/lib
+ * @run main FileUtilsTest
+ */
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import jdk.test.lib.Asserts;
+import jdk.test.lib.util.FileUtils;
+
+public class FileUtilsTest {
+
+    public static void main(String[] args) throws Exception {
+        // Replace with same line
+        test("a", 1, 1, null, "a", "a\n");
+        // Replace with different line
+        test("a", 1, 1, null, "z", "z\n");
+        // Replace with same line based on line match
+        test("a", 1, 1, "a", "a", "a\n");
+        // Replace with different line based on line match
+        test("a", 1, 1, "a", "z", "z\n");
+        // Replace single line with multiple lines
+        test("a", 1, 1, null, "x\ny\nz", "x\ny\nz\n");
+        // Replace single line with multiple lines based on lines match
+        test("a", 1, 1, "a", "x\ny\nz", "x\ny\nz\n");
+        // Replace all lines
+        test("a\nb\nc", 1, 3, null, "x\ny\nz", "x\ny\nz\n");
+        // Replace all lines based on lines match
+        test("a\nb\nc", 1, 3, "a\nb\nc", "x\ny\nz", "x\ny\nz\n");
+        // Replace all lines with single line based on lines match
+        test("a\nb\nc", 1, 3, "a\nb\nc", "z", "z\n");
+        // Replace single line
+        test("a\nb\nc", 1, 1, null, "z", "z\nb\nc\n");
+        // Replace single line based on line match
+        test("a\nb\nc", 1, 1, "a", "z", "z\nb\nc\n");
+        // Replace multiple lines
+        test("a\nb\nc", 1, 2, null, "z", "z\nc\n");
+        // Replace multiple lines based on line match
+        test("a\nb\nc", 1, 2, "a\nb", "z", "z\nc\n");
+        // Replace multiple lines based on line match
+        test("a\nb\nc", 1, 2, "a\nb", "x\ny\nz", "x\ny\nz\nc\n");
+
+        // Test with space characters
+        // Replace with space line
+        test("\n", 1, 1, null, " ", " \n");
+        // Replace empty line with another line based on line match
+        test("\n", 1, 1, " ", "a", "a\n");
+        // Replace with space line
+        test(" \na\nb\nc", 1, 1, null, "a", "a\na\nb\nc\n");
+        // Replace empty line with different line based on line match
+        test(" \na\nb\nc", 1, 1, " ", "a", "a\na\nb\nc\n");
+        // Replace range of lines with space to different lines based on line match
+        test(" \na\nb\nc", 1, 2, " \na", "x\ny\nz", "x\ny\nz\nb\nc\n");
+
+        test("a\nb\nc\n", 1, 2, "a\nb", "1\n2", "1\n2\nc\n");
+        test("a\nb\nc\n", 1, 2, " a\nb", "1\n2", "1\n2\nc\n"); // free to add spaces around a line in from
+        test("a\nb\nc\n", 1, 2, "a \nb", "1\n2", "1\n2\nc\n");
+        test("a\nb\nc\n", 1, 2, "a\n b ", "1\n2", "1\n2\nc\n");
+        test("a\nb\nc\n", 1, 2, "\na\nb", "1\n2", "1\n2\nc\n"); // free to add empty lines at both ends of from
+        test("a\nb\nc\n", 1, 2, "a\nb\n", "1\n2", "1\n2\nc\n");
+        test("a\nb\nc\n", 1, 2, "\na\nb\n", "1\n2", "1\n2\nc\n");
+        test("a\nb\nc\n", 1, 2, "\n\na\nb\n\n", "1\n2", "1\n2\nc\n");
+        test("a\nb\nc\n", 1, 2, "a\nb", "1\n2\n", "1\n2\nc\n"); // ok to add a new line at end of to
+        test("a\nb\nc\n", 1, 2, "a\nb", "1\n2\n\n", "1\n2\n\nc\n"); // more will change result
+        test("a\nb\nc\n", 1, 2, "a\nb", "\n1\n2", "\n1\n2\nc\n");
+        test("a\nb\nc\n", 1, 2, "a\n\nb", "1\n2\n", null); // no extra new line inside
+        test("a\nb\nc\n", 1, 2, "ab", "1\n2\n", null); // new line inside must preserve
+        test("a\nb\nc\n", 1, 2, "a", "1\n2\n", null); // must be all
+        test("a\nb\nc\n", 1, 2, "b", "1\n2\n", null); // must be all
+
+        test("a\nb\nc\n", 1, 2, "a\nb", "", "c\n"); // just remove
+        test("a\nb\nc\n", 1, 0, "", "1\n2", "1\n2\na\nb\nc\n"); // just add
+
+        // Mismatched range with "replace" lines Tests
+        // Replace all lines with mismatched line
+        test("a", 1, 1, "z", "z", null);
+        // Replace all lines with mismatched lines
+        test("a\nb\nc", 1, 3, "x\ny\nz", "x\ny\nz", null);
+        // Replace single line with mismatched line
+        test("a\nb\nc", 1, 1, "z", "z", null);
+        // Replace a range of lines with mismatched lines
+        test("a\nb\nc", 1, 3, "ab", "x\ny\nz", null);
+    }
+
+    private static void test(String content, int from, int to, String replace,
+                String replaceTo, String expected) throws IOException {
+        String name = "Test-" + new Exception().getStackTrace()[1].getLineNumber();
+        Path path = Files.writeString(Paths.get(name), content);
+        String output = null;
+        try {
+            FileUtils.patch(path, from, to, replace, replaceTo);
+            output = Files.readString(path);
+        } catch (IOException e) {
+            // output is null
+        }
+        Asserts.assertEQ(output, (expected != null) ? expected.replaceAll("\n", System.lineSeparator()) : null);
+    }
+}

test/lib/jdk/test/lib/util/FileUtils.java

@@ -47,7 +47,7 @@
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicReference;
-
+import java.util.stream.Collectors;
 import jdk.test.lib.Platform;
 
 import com.sun.management.UnixOperatingSystemMXBean;
@@ -377,6 +377,44 @@ public static long getProcessHandleCount() {
         }
     }
 
+    /**
+     * Patches a part of a file.
+     *
+     * @param path the file
+     * @param fromLine the first line to patch. This is the number you see in an editor, 1-based, inclusive.
+     * @param toLine the last line to patch. This is the number you see in an editor, inclusive.
+     *               Set {@code toLine} to {@code fromLine - 1} if you only want to insert lines.
+     * @param from lines to remove, used to ensure the correct lines are removed. Can be multiple lines or empty.
+     *            It's compared to existing lines with all lines trimmed and no new lines at both ends. Ignored if null.
+     * @param to the newly added lines, can be multiple lines or empty. New line at end is optional. Cannot be null.
+     * @throws IOException if there's an I/O error or {@code from} does not match the existing lines
+     * @throws IndexOutOfBoundsException if {@code fromLine} or {@code toLine} is invalid
+     */
+    public static void patch(Path path, int fromLine, int toLine, String from, String to) throws IOException {
+        var lines = Files.readAllLines(path);
+        // The next line does a from/to as well
+        var subList = lines.subList(fromLine - 1, toLine);
+        if (from != null) {
+            // Each line is trimmed so caller needs not care about indentation.
+            // Caller also needs not care about new lines on both ends.
+            // New lines inside are preserved.
+            String actuallyRemoved = subList.stream()
+                            .map(String::trim)
+                            .collect(Collectors.joining("\n")).trim();
+            String wantToRemove = from.lines()
+                            .map(String::trim)
+                            .collect(Collectors.joining("\n")).trim();
+            if (!actuallyRemoved.equals(wantToRemove)) {
+                throw new IOException("Removed not the same: ["
+                        + String.join("\\n", subList) + "] and ["
+                        + from.replaceAll("\\n", "\\\\n") + "]");
+            }
+        }
+        subList.clear();
+        lines.addAll(fromLine - 1, to.lines().toList());
+        Files.write(path, lines);
+    }
+
     private static native long getWinProcessHandleCount();
 
     // Possible command locations and arguments