[PATCH try2] completion: prompt: use generic colors

[Felipe Contreras <felipe.contreras@gmail.com>]

When the prompt command mode was introduced in 1bfc51ac81 (Allow
__git_ps1 to be used in PROMPT_COMMAND, 2012-10-10) the assumption was
that it was necessary in order to properly add colors to PS1 in bash,
but this wasn't true.

It's true that the \[ \] markers add the information needed to properly
calculate the width of the prompt, and they have to be added directly to
PS1, a function returning them doesn't work.

But that is because bash coverts the \[ \] markers in PS1 to \001 \002,
which is what readline ultimately needs in order to calculate the width.

We don't need bash to do this conversion, we can use \001 \002
ourselves, and then the prompt command mode is not necessary to display
colors.

This is what functions returning colors are supposed to do [1].

[1] http://mywiki.wooledge.org/BashFAQ/053

Signed-off-by: Felipe Contreras <felipe.contreras@gmail.com>
---
 contrib/completion/git-prompt.sh | 19 +++++++------------
 t/t9903-bash-prompt.sh           |  8 ++++----
 2 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/contrib/completion/git-prompt.sh b/contrib/completion/git-prompt.sh
index 57972c2845..76ee4ab1e5 100644
--- a/contrib/completion/git-prompt.sh
+++ b/contrib/completion/git-prompt.sh
@@ -100,9 +100,7 @@
 #
 # If you would like a colored hint about the current dirty state, set
 # GIT_PS1_SHOWCOLORHINTS to a nonempty value. The colors are based on
-# the colored output of "git status -sb" and are available only when
-# using __git_ps1 for PROMPT_COMMAND or precmd in Bash,
-# but always available in Zsh.
+# the colored output of "git status -sb".
 #
 # If you would like __git_ps1 to do nothing in the case when the current
 # directory is set up to be ignored by git, then set
@@ -259,12 +257,12 @@ __git_ps1_colorize_gitstring ()
 		local c_lblue='%F{blue}'
 		local c_clear='%f'
 	else
-		# Using \[ and \] around colors is necessary to prevent
+		# Using \001 and \002 around colors is necessary to prevent
 		# issues with command line editing/browsing/completion!
-		local c_red='\[\e[31m\]'
-		local c_green='\[\e[32m\]'
-		local c_lblue='\[\e[1;34m\]'
-		local c_clear='\[\e[0m\]'
+		local c_red=$'\001\e[31m\002'
+		local c_green=$'\001\e[32m\002'
+		local c_lblue=$'\001\e[1;34m\002'
+		local c_clear=$'\001\e[0m\002'
 	fi
 	local bad_color=$c_red
 	local ok_color=$c_green
@@ -574,11 +572,8 @@ __git_ps1 ()
 		b="\${__git_ps1_branch_name}"
 	fi
 
-	# NO color option unless in PROMPT_COMMAND mode or it's Zsh
 	if [ -n "${GIT_PS1_SHOWCOLORHINTS-}" ]; then
-		if [ $pcmode = yes ] || [ -n "${ZSH_VERSION-}" ]; then
-			__git_ps1_colorize_gitstring
-		fi
+		__git_ps1_colorize_gitstring
 	fi
 
 	local f="$h$w$i$s$u$p"
diff --git a/t/t9903-bash-prompt.sh b/t/t9903-bash-prompt.sh
index d459fae655..d667dda654 100755
--- a/t/t9903-bash-prompt.sh
+++ b/t/t9903-bash-prompt.sh
@@ -13,10 +13,10 @@ export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME
 . "$GIT_BUILD_DIR/contrib/completion/git-prompt.sh"
 
 actual="$TRASH_DIRECTORY/actual"
-c_red='\\[\\e[31m\\]'
-c_green='\\[\\e[32m\\]'
-c_lblue='\\[\\e[1;34m\\]'
-c_clear='\\[\\e[0m\\]'
+c_red='\001\e[31m\002'
+c_green='\001\e[32m\002'
+c_lblue='\001\e[1;34m\002'
+c_clear='\001\e[0m\002'
 
 test_expect_success 'setup for prompt tests' '
 	git init otherrepo &&
-- 
2.39.2