This reverts commit 4d344f712298364c836038b641625b3407db2fc3. The GCC

testsuite still uses diff.

	2016-03-15  Ben Elliston  <bje@gnu.org>

	* lib/utils.exp (diff): Remove proc.
	* doc/ref.xml: Update documentation.
	* doc/dejagnu.texi: Regenerate.
	* NEWS: Update.

5 files changed, 135 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index 0bddd16..125f3d4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2016-03-16  Ben Elliston  <bje@gnu.org>
+
+	Revert this change (the GCC testsuite uses diff):
+
+	2016-03-15  Ben Elliston  <bje@gnu.org>
+
+	* lib/utils.exp (diff): Remove proc.
+	* doc/ref.xml: Update documentation.
+	* doc/dejagnu.texi: Regenerate.
+	* NEWS: Update.
+
 2016-03-15  Ben Elliston  <bje@gnu.org>
 
 	* testsuite/runtest.all/options.exp: Properly clean up log files
diff --git a/NEWS b/NEWS
index 3cedf64..1d3f672 100644
--- a/NEWS
+++ b/NEWS
@@ -10,8 +10,8 @@ Changes since 1.5.3:
    2 if an exception is raised by the Tcl interpreter.
 3. runtest now exits with the standard exit codes of programs that are
    terminated by the SIGINT, SIGTERM and SIGQUIT signals.
-4. The user-visible utility procedures `absolute', `psource', `slay'
-   and `diff' have been removed.  If a testsuite uses any of these
+4. The user-visible utility procedures `absolute', `psource' and
+   `slay' have been removed.  If a testsuite uses any of these
    procedures, a copy of the procedure should be made and placed in
    the lib directory of the testsuite.
 5. Support was added for testing the D compiler.
diff --git a/doc/dejagnu.texi b/doc/dejagnu.texi
index c0c80ba..99dd8f1 100644
--- a/doc/dejagnu.texi
+++ b/doc/dejagnu.texi
@@ -5414,6 +5414,7 @@ tool, and its version number.
 * Grep Procedure: grep procedure.
 * Prune Procedure: prune procedure.
 * Runtest_file_p Procedure: runtest_file_p procedure.
+* Diff Procedure: diff procedure.
 * Setenv Procedure: setenv procedure.
 * unsetenv Procedure: unsetenv procedure.
 * Getenv Procedure: getenv procedure.
@@ -5543,7 +5544,7 @@ the next release of DejaGnu.  If a testsuite uses this
 procedure, a copy of the procedure should be made and placed
 in the lib directory of the testsuite.
 
-@node runtest_file_p procedure, setenv procedure, prune procedure, Utility Procedures
+@node runtest_file_p procedure, diff procedure, prune procedure, Utility Procedures
 @subsubsection Runtest_file_p Procedure
 
 Search @emph{runtest}s for
@@ -5576,7 +5577,30 @@ The list of patterns to compare against.
 The test case filename.
 @end table
 
-@node setenv procedure, unsetenv procedure, runtest_file_p procedure, Utility Procedures
+@node diff procedure, setenv procedure, runtest_file_p procedure, Utility Procedures
+@subsubsection Diff Procedure
+
+Compares the two files and returns a @emph{1} if
+they match, or a @emph{0} if they don't. If
+@code{verbose} is set, then it'll print the differences to
+the screen.
+
+@quotation
+
+@t{@b{diff}(@i{file_1}
+@i{file_2});}
+@end quotation
+
+@table @asis
+
+@item @code{file_1}
+The first file to compare.
+
+@item @code{file_2}
+The second file to compare.
+@end table
+
+@node setenv procedure, unsetenv procedure, diff procedure, Utility Procedures
 @subsubsection Setenv Procedure
 
 Sets the environment variable @emph{var} to the
diff --git a/doc/ref.xml b/doc/ref.xml
index 0276334..05013ae 100644
--- a/doc/ref.xml
+++ b/doc/ref.xml
@@ -3620,6 +3620,33 @@
 	</variablelist>
 	</sect4>
 
+	<sect4 id="diff" xreflabel="diff procedure">
+	  <title>Diff Procedure</title>
+
+	  <para>Compares the two files and returns a <emphasis>1</emphasis> if
+	  they match, or a <emphasis>0</emphasis> if they don't. If
+	  <symbol>verbose</symbol> is set, then it'll print the differences to
+	  the screen.</para>
+
+	<funcsynopsis role="tcl">
+          <funcprototype>
+            <funcdef><function>diff</function></funcdef>
+	    <paramdef><parameter>file_1</parameter>
+	    <parameter>file_2</parameter></paramdef>
+           </funcprototype>
+	</funcsynopsis>
+	<variablelist>
+          <varlistentry>
+	    <term><parameter>file_1</parameter></term>
+	    <listitem><para>The first file to compare.</para></listitem>
+          </varlistentry>
+          <varlistentry>
+	    <term><parameter>file_2</parameter></term>
+	    <listitem><para>The second file to compare.</para></listitem>
+          </varlistentry>
+	</variablelist>
+	</sect4>
+
 	<sect4 id="setenv" xreflabel="setenv procedure">
 	  <title>Setenv Procedure</title>
 
diff --git a/lib/utils.exp b/lib/utils.exp
index 8db12b8..505ad18 100644
--- a/lib/utils.exp
+++ b/lib/utils.exp
@@ -250,6 +250,75 @@ proc runtest_file_p { runtests testcase } {
 }
 
 
+# Compares two files line-by-line
+#     returns 1 it the files match,
+#     returns 0 if there was a file error,
+#     returns -1 if they didn't match.
+#
+proc diff { file_1 file_2 } {
+    set eof -1
+    set differences 0
+
+    if {[file exists ${file_1}]} {
+	set file_a [open ${file_1} r]
+	fconfigure $file_a -encoding binary
+    } else {
+	warning "${file_1} doesn't exist"
+	return 0
+    }
+
+    if {[file exists ${file_2}]} {
+	set file_b [open ${file_2} r]
+	fconfigure $file_b -encoding binary
+    } else {
+	warning "${file_2} doesn't exist"
+	return 0
+    }
+
+    verbose "# Diff'ing: ${file_1} ${file_2}" 1
+
+    set list_a ""
+    while { [gets ${file_a} line] != ${eof} } {
+	if {[regexp "^#.*$" ${line}]} {
+	    continue
+	} else {
+	    lappend list_a ${line}
+	}
+    }
+    close ${file_a}
+
+    set list_b ""
+    while { [gets ${file_b} line] != ${eof} } {
+	if {[regexp "^#.*$" ${line}]} {
+	    continue
+	} else {
+	    lappend list_b ${line}
+	}
+    }
+    close ${file_b}
+    for { set i 0 } { $i < [llength $list_a] } { incr i } {
+	set line_a [lindex ${list_a} ${i}]
+	set line_b [lindex ${list_b} ${i}]
+
+	if {[string compare ${line_a} ${line_b}]} {
+	    verbose -log "line #${i}" 2
+	    verbose -log "\< ${line_a}" 2
+	    verbose -log "\> ${line_b}" 2
+	    set differences -1
+	}
+    }
+
+    if { $differences == -1 || [llength ${list_a}] != [llength ${list_b}] } {
+	verbose "Files not the same" 2
+	set differences -1
+    } else {
+	verbose "Files are the same" 2
+	set differences 1
+    }
+    return ${differences}
+}
+
+#
 # Set an environment variable
 #
 proc setenv { var val } {