preserve linefeed-style in propertyfile task. PR 50049

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@1027179 13f79535-47bb-0310-9956-ffa450edef68

WHATSNEW

@@ -183,6 +183,10 @@ Fixed bugs:
    wrong.
    Bugzilla Report 45227.
 
+ * <propertyfile> didn't preserve the original linefeed style when
+   updating a file.
+   Bugzilla Report 50049.
+
 Other changes:
 --------------
 

docs/manual/Tasks/propertyfile.html

@@ -32,9 +32,14 @@ very useful when wanting to make unattended modifications to
 configuration files for application servers and
 applications. Currently, the task maintains a working property file
 with the ability to add properties or make changes to existing
-ones. Since Ant 1.8.0 comments and layout of the original properties
+ones. <em>Since Ant 1.8.0</em> comments and layout of the original properties
 file are preserved.</p>
 
+<p><em>Since Ant 1.8.2</em> the linefeed-style of the original file
+  will be preserved as well, as long as style used to be consistent.
+  In general, linefeeds of the updated file will be the same as the
+  first linefeed found when reading it.</p>
+
 <hr>
 <h2><a name="proptask">PropertyFile Task</a></h2>
 <h3>Parameters</h3>

src/main/org/apache/tools/ant/util/LayoutPreservingProperties.java

@@ -27,6 +27,7 @@ import java.io.InputStreamReader;
 import java.io.OutputStream;
 import java.io.OutputStreamWriter;
 import java.io.PrintStream;
+import java.io.PushbackReader;
 import java.util.ArrayList;
 import java.util.Date;
 import java.util.HashMap;
@@ -78,7 +79,7 @@ import java.util.Properties;
  * although the key-value pair <code>beta=two</code> is removed.</p>
  */
 public class LayoutPreservingProperties extends Properties {
-    private static final String LS = System.getProperty("line.separator");
+    private String LS = StringUtils.LINE_SEP;
 
     /**
      * Logical lines have escaping and line continuation taken care
@@ -310,14 +311,15 @@ public class LayoutPreservingProperties extends Properties {
      */
     private String readLines(InputStream is) throws IOException {
         InputStreamReader isr = new InputStreamReader(is, ResourceUtils.ISO_8859_1);
-        BufferedReader br = new BufferedReader(isr);
+        PushbackReader pbr = new PushbackReader(isr, 1);
 
         if (logicalLines.size() > 0) {
             // we add a blank line for spacing
             logicalLines.add(new Blank());
         }
 
-        String s = br.readLine();
+        String s = readFirstLine(pbr);
+        BufferedReader br = new BufferedReader(pbr);
 
         boolean continuation = false;
         boolean comment = false;
@@ -366,6 +368,46 @@ public class LayoutPreservingProperties extends Properties {
         return fileBuffer.toString();
     }
 
+    /**
+     * Reads the first line and determines the EOL-style of the file
+     * (relies on the style to be consistent, of course).
+     *
+     * <p>Sets LS as a side-effect.</p>
+     *
+     * @return the first line without any line separator, leaves the
+     * reader positioned after the first line separator
+     *
+     * @since Ant 1.8.2
+     */
+    private String readFirstLine(PushbackReader r) throws IOException {
+        StringBuffer sb = new StringBuffer(80);
+        int ch = r.read();
+        boolean hasCR = false;
+        // when reaching EOF before the first EOL, assume native line
+        // feeds
+        LS = StringUtils.LINE_SEP;
+
+        while (ch >= 0) {
+            if (hasCR && ch != '\n') {
+                // line feed is sole CR
+                r.unread(ch);
+                break;
+            }
+
+            if (ch == '\r') {
+                LS = "\r";
+                hasCR = true;
+            } else if (ch == '\n') {
+                LS = hasCR ? "\r\n" : "\n";
+                break;
+            } else {
+                sb.append((char) ch);
+            }
+            ch = r.read();
+        }
+        return sb.toString();
+    }
+
     /**
      * Returns <code>true</code> if the line represented by
      * <code>s</code> is to be continued on the next line of the file,

src/tests/antunit/taskdefs/optional/propertyfilelayout-test.xml

@@ -241,4 +241,49 @@ x=1
     <au:assertPropertyEquals name="tail.out" value="${tail.in}"/>
   </target>
 
+
+  <target name="testPreservesDosLineEnds" depends="setUp"
+          description="https://issues.apache.org/bugzilla/show_bug.cgi?id=50049">
+    <property name="test.txt" location="${output}/test.txt"/>
+    <echo file="${test.txt}"><![CDATA[
+bbb=val2
+aaa=val1
+]]></echo>
+    <fixcrlf eol="dos" file="${test.txt}"/>
+    <propertyfile file="${test.txt}" comment="${header}"/>
+    <copy file="${test.txt}" tofile="${test.txt}.expected"/>
+    <fixcrlf eol="dos" file="${test.txt}.expected"/>
+    <au:assertFilesMatch expected="${test.txt}.expected"
+                         actual="${test.txt}"/>
+  </target>
+
+  <target name="testPreservesUnixLineEnds" depends="setUp"
+          description="https://issues.apache.org/bugzilla/show_bug.cgi?id=50049">
+    <property name="test.txt" location="${output}/test.txt"/>
+    <echo file="${test.txt}"><![CDATA[
+bbb=val2
+aaa=val1
+]]></echo>
+    <fixcrlf eol="unix" file="${test.txt}"/>
+    <propertyfile file="${test.txt}" comment="${header}"/>
+    <copy file="${test.txt}" tofile="${test.txt}.expected"/>
+    <fixcrlf eol="unix" file="${test.txt}.expected"/>
+    <au:assertFilesMatch expected="${test.txt}.expected"
+                         actual="${test.txt}"/>
+  </target>
+
+  <target name="testPreservesMacLineEnds" depends="setUp"
+          description="https://issues.apache.org/bugzilla/show_bug.cgi?id=50049">
+    <property name="test.txt" location="${output}/test.txt"/>
+    <echo file="${test.txt}"><![CDATA[
+bbb=val2
+aaa=val1
+]]></echo>
+    <fixcrlf eol="mac" file="${test.txt}"/>
+    <propertyfile file="${test.txt}" comment="${header}"/>
+    <copy file="${test.txt}" tofile="${test.txt}.expected"/>
+    <fixcrlf eol="mac" file="${test.txt}.expected"/>
+    <au:assertFilesMatch expected="${test.txt}.expected"
+                         actual="${test.txt}"/>
+  </target>
 </project>