1 /*

     2  * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  */

    23 

    24 /*

    25  * @test

    26  * @summary Unit tests for String#indent

    27  * @run main Indent

    28  */

    29 

    30 import java.util.Arrays;

    31 import java.util.List;

    32 import java.util.stream.Collectors;

    33 import java.util.stream.Stream;

    34 

    35 public class Indent {

    36     static final List<String> ENDS = List.of("", "\n", "   \n", "\n\n", "\n\n\n");

    37     static final List<String> MIDDLES = List.of(

    38             "",

    39             "xyz",

    40             "   xyz",

    41             "      xyz",

    42             "xyz   ",

    43             "   xyz   ",

    44             "      xyz   ",

    45             "xyz\u2022",

    46             "   xyz\u2022",

    47             "xyz\u2022   ",

    48             "   xyz\u2022   ",

    49             "   // comment"

    50     );

    51 

    52     public static void main(String[] args) {

    53         test1();

    54     }

    55 

    56     /*

    57      * Test String#indent(int n) functionality.

    58      */

    59     static void test1() {

    60         for (int adjust : new int[] {-8, -7, -4, -3, -2, -1, 0, 1, 2, 3, 4, 7, 8}) {

    61             for (String prefix : ENDS) {

    62                 for (String suffix : ENDS) {

    63                     for (String middle : MIDDLES) {

    64                         String input = prefix + "   abc   \n" + middle + "\n   def   \n" + suffix;

    65                         String output = input.indent(adjust);

    66 

    67                         Stream<String> stream = input.lines();

    68                         if (adjust > 0) {

    69                             final String spaces = " ".repeat(adjust);

    70                             stream = stream.map(s -> s.isBlank() ? s : spaces + s);

    71                         } else if (adjust < 0) {

    72                             stream = stream.map(s -> s.substring(Math.min(-adjust, indexOfNonWhitespace(s))));

    73                         }

    74                         String expected = stream.collect(Collectors.joining("\n", "", "\n"));

    75 

    76                         if (!output.equals(expected)) {

    77                             report("String::indent(int n)",

    78                                     "Result indentation not as expected", expected, output);

    79                         }

    80                     }

    81                 }

    82             }

    83         }

    84     }

    85 

    86     public static int indexOfNonWhitespace(String s) {

    87         int left = 0;

    88         while (left < s.length()) {

    89             char ch = s.charAt(left);

    90             if (ch != ' ' && ch != '\t' && !Character.isWhitespace(ch)) {

    91                 break;

    92             }

    93             left++;

    94         }

    95         return left;

    96     }

    97 

    98 

    99     private static String[] getBody(String[] inLines) {

   100         int from = -1, to = -1;

   101         for (int i = 0; i < inLines.length; i++) {

   102             String line = inLines[i];

   103             if (!line.isBlank()) {

   104                 if (from == -1) {

   105                     from = i;

   106                 }

   107                 to = i + 1;

   108             }

   109         }

   110         return Arrays.copyOfRange(inLines, from, to);

   111     }

   112 

   113     /*

   114      * Report difference in result.

   115      */

   116     static void report(String test, String message, String input, String output) {

   117         System.err.println("Testing " + test + ": " + message);

   118         System.err.println();

   119         System.err.println("Input: length = " + input.length());

   120         System.err.println("_".repeat(40));

   121         System.err.print(input.replaceAll(" ", "."));

   122         System.err.println("_".repeat(40));

   123         System.err.println();

   124         System.err.println("Output: length = " + output.length());

   125         System.err.println("_".repeat(40));

   126         System.err.print(output.replaceAll(" ", "."));

   127         System.err.println("_".repeat(40));

   128         throw new RuntimeException();

   129     }

   130 }