[binutils-gdb] [gdb/cli] Don't let python colorize strip leading newlines

[binutils-gdb] [gdb/cli] Don't let python colorize strip leading newlines

[Tom de Vries]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=bdfc1e8a0b176257bfc700de755463d3aaf69849

commit bdfc1e8a0b176257bfc700de755463d3aaf69849
Author: Tom de Vries <tdevries@suse.de>
Date:   Fri Apr 10 09:29:52 2020 +0200

    [gdb/cli] Don't let python colorize strip leading newlines
    
    Consider the test-case gdb.base/async.exp.  Using the executable, I run to
    main, and land on a line advertised as line 26:
    ...
    $ gdb outputs/gdb.base/async/async -ex start
    Reading symbols from outputs/gdb.base/async/async...
    Temporary breakpoint 1 at 0x4004e4: file gdb.base/async.c, line 26.
    Starting program: outputs/gdb.base/async/async
    
    Temporary breakpoint 1, main () at gdb.base/async.c:26
    26       y = foo ();
    ...
    
    But actually, the line turns out to be line 28:
    ...
    $ cat -n gdb.base/async.c
        ...
        26   y = 2;
        27   z = 9;
        28   y = foo ();
    ...
    
    This is caused by the following: the python colorizer initializes the lexer
    with default options (no second argument to get_lexer_for_filename):
    ...
        def colorize(filename, contents):
            # Don't want any errors.
            try:
                lexer = lexers.get_lexer_for_filename(filename)
                formatter = formatters.TerminalFormatter()
                return highlight(contents, lexer, formatter)
    ...
    which include option stripnl=True, which strips leading and trailing newlines.
    
    This causes the python colorizer to strip the two leading newlines of async.c.
    
    Fix this by initializing the lexer with stripnl=False.
    
    Build and reg-tested on x86_64-linux.
    
    gdb/ChangeLog:
    
    2020-04-10  Tom de Vries  <tdevries@suse.de>
    
            PR cli/25808
            * python/lib/gdb/__init__.py: Initialize lexer with stripnl=False.
    
    gdb/testsuite/ChangeLog:
    
    2020-04-10  Tom de Vries  <tdevries@suse.de>
    
            PR cli/25808
            * gdb.base/style.c: Add leading newlines.
            * gdb.base/style.exp: Use gdb_get_line_number to get specific lines.
            Check listing of main's one-line body.

Diff:
---
 gdb/ChangeLog                    | 5 +++++
 gdb/python/lib/gdb/__init__.py   | 2 +-
 gdb/testsuite/ChangeLog          | 7 +++++++
 gdb/testsuite/gdb.base/style.c   | 4 ++++
 gdb/testsuite/gdb.base/style.exp | 8 +++++++-
 5 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 050c9b264e4..2c347fc473d 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2020-04-10  Tom de Vries  <tdevries@suse.de>
+
+	PR cli/25808
+	* python/lib/gdb/__init__.py: Initialize lexer with stripnl=False.
+
 2020-04-09  Simon Marchi  <simon.marchi@polymtl.ca>
 
 	* MAINTAINERS (Global Maintainers): Add Tom de Vries.
diff --git a/gdb/python/lib/gdb/__init__.py b/gdb/python/lib/gdb/__init__.py
index a1aac007923..3dfb51b2af9 100644
--- a/gdb/python/lib/gdb/__init__.py
+++ b/gdb/python/lib/gdb/__init__.py
@@ -216,7 +216,7 @@ try:
     def colorize(filename, contents):
         # Don't want any errors.
         try:
-            lexer = lexers.get_lexer_for_filename(filename)
+            lexer = lexers.get_lexer_for_filename(filename, stripnl=False)
             formatter = formatters.TerminalFormatter()
             return highlight(contents, lexer, formatter)
         except:
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 16b982bfc9c..023f5a815c6 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,10 @@
+2020-04-10  Tom de Vries  <tdevries@suse.de>
+
+	PR cli/25808
+	* gdb.base/style.c: Add leading newlines.
+	* gdb.base/style.exp: Use gdb_get_line_number to get specific lines.
+	Check listing of main's one-line body.
+
 2020-04-08  Tom de Vries  <tdevries@suse.de>
 
 	* lib/gdb.exp (psymtabs_p): New proc.
diff --git a/gdb/testsuite/gdb.base/style.c b/gdb/testsuite/gdb.base/style.c
index cb75b3b915e..4e0e0dfcd77 100644
--- a/gdb/testsuite/gdb.base/style.c
+++ b/gdb/testsuite/gdb.base/style.c
@@ -1,3 +1,7 @@
+
+
+/* The leading newlines here are intentional, do not remove.  They are used to
+   test that the source highlighter doesn't strip them.  */
 /* Copyright 2018-2020 Free Software Foundation, Inc.
 
    This program is free software; you can redistribute it and/or modify
diff --git a/gdb/testsuite/gdb.base/style.exp b/gdb/testsuite/gdb.base/style.exp
index 47ef8c93c7c..1071b023aa6 100644
--- a/gdb/testsuite/gdb.base/style.exp
+++ b/gdb/testsuite/gdb.base/style.exp
@@ -39,6 +39,11 @@ save_vars { env(TERM) } {
 	return
     }
 
+    # Check that the source highlighter has not stripped away the leading
+    # newlines.
+    set main_line [gdb_get_line_number "break here"]
+    gdb_test "list $main_line,$main_line" "return.*some_called_function.*"
+
     gdb_test_no_output "set style enabled on"
 
     set main_expr [style main function]
@@ -79,8 +84,9 @@ save_vars { env(TERM) } {
     }
 
     if {$test_macros} {
+	set macro_line [gdb_get_line_number "\#define SOME_MACRO"]
 	gdb_test "info macro SOME_MACRO" \
-	    "Defined at $base_file_expr:16\r\n#define SOME_MACRO 23"
+	    "Defined at $base_file_expr:$macro_line\r\n#define SOME_MACRO 23"
     }
 
     set func [style some_called_function function]