mergetool--lib: simplify API usage by removing more global variables

The mergetool--lib scriplet was tricky to use because it relied upon
the existance of several global shell variables.  This removes more
global variables so that things are simpler for callers.

A side effect is that some variables are recomputed each time
run_merge_tool() is called, but the overhead for recomputing
them is justified by the simpler implementation.

Signed-off-by: David Aguilar <davvid@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/git-mergetool--lib.txt b/Documentation/git-mergetool--lib.txt
index 3d57031d78d9e274890ab2264adcbc95980646d0..78eb03f0ae864f67faac55f450bf0fd2be3416b3 100644 (file)
--- a/Documentation/git-mergetool--lib.txt
+++ b/Documentation/git-mergetool--lib.txt
@@ -7,7 +7,7 @@ git-mergetool--lib - Common git merge tool shell scriptlets
 
 SYNOPSIS
 --------
-'. "$(git --exec-path)/git-mergetool--lib"'
+'TOOL_MODE=(diff|merge) . "$(git --exec-path)/git-mergetool--lib"'
 
 DESCRIPTION
 -----------
@@ -20,14 +20,14 @@ The 'git-mergetool--lib' scriptlet is designed to be sourced (using
 `.`) by other shell scripts to set up functions for working
 with git merge tools.
 
-Before sourcing it, your script should set up a few variables;
-`TOOL_MODE` is used to define the operation mode for various
-functions.  'diff' and 'merge' are valid values.
+Before sourcing 'git-mergetool--lib', your script must set `TOOL_MODE`
+to define the operation mode for the functions listed below.
+'diff' and 'merge' are valid values.
 
 FUNCTIONS
 ---------
 get_merge_tool::
-       returns a merge tool
+       returns a merge tool.
 
 get_merge_tool_cmd::
        returns the custom command for a merge tool.
@@ -38,10 +38,8 @@ get_merge_tool_path::
 run_merge_tool::
        launches a merge tool given the tool name and a true/false
        flag to indicate whether a merge base is present.
-       '$merge_tool', '$merge_tool_path', and for custom commands,
-       '$merge_tool_cmd', must be defined prior to calling
-       run_merge_tool.  Additionally, '$MERGED', '$LOCAL', '$REMOTE',
-       and '$BASE' must be defined for use by the merge tool.
+       '$MERGED', '$LOCAL', '$REMOTE', and '$BASE' must be defined
+       for use by the merge tool.
 
 Author
 ------

diff --git a/git-difftool--helper.sh b/git-difftool--helper.sh
index b4500368c3268bb26aa22ccf75b9b2fd4bc94df1..57e8e3256d7b6578cda37815163d8945431aa6db 100755 (executable)
--- a/git-difftool--helper.sh
+++ b/git-difftool--helper.sh
@@ -47,9 +47,9 @@ launch_merge_tool () {
 test -n "$GIT_MERGE_TOOL" && merge_tool="$GIT_MERGE_TOOL"
 test -n "$GIT_DIFF_TOOL" && merge_tool="$GIT_DIFF_TOOL"
 
-merge_tool=$(get_merge_tool "$merge_tool") || exit
-merge_tool_cmd="$(get_merge_tool_cmd "$merge_tool")"
-merge_tool_path="$(get_merge_tool_path "$merge_tool")" || exit
+if test -z "$merge_tool"; then
+       merge_tool="$(get_merge_tool)" || exit
+fi
 
 # Launch the merge tool on each path provided by 'git diff'
 while test $# -gt 6

diff --git a/git-mergetool--lib.sh b/git-mergetool--lib.sh
index c5db24e45dd9538528c64bcb3b0bd8ebf71a6771..a16a2795d70779365212c09b6d0dd42d1746842b 100644 (file)
--- a/git-mergetool--lib.sh
+++ b/git-mergetool--lib.sh
@@ -8,25 +8,20 @@ merge_mode() {
 }
 
 translate_merge_tool_path () {
-       if test -n "$2"; then
-               echo "$2"
-       else
-               case "$1" in
-               vimdiff)
-                       path=vim
-                       ;;
-               gvimdiff)
-                       path=gvim
-                       ;;
-               emerge)
-                       path=emacs
-                       ;;
-               *)
-                       path="$1"
-                       ;;
-               esac
-               echo "$path"
-       fi
+       case "$1" in
+       vimdiff)
+               echo vim
+               ;;
+       gvimdiff)
+               echo gvim
+               ;;
+       emerge)
+               echo emacs
+               ;;
+       *)
+               echo "$1"
+               ;;
+       esac
 }
 
 check_unchanged () {
@@ -69,15 +64,22 @@ valid_tool () {
 }
 
 get_merge_tool_cmd () {
-       diff_mode &&
-       custom_cmd="$(git config difftool.$1.cmd)"
-       test -z "$custom_cmd" &&
-       custom_cmd="$(git config mergetool.$1.cmd)"
-       test -n "$custom_cmd" &&
-       echo "$custom_cmd"
+       # Prints the custom command for a merge tool
+       if test -n "$1"; then
+               merge_tool="$1"
+       else
+               merge_tool="$(get_merge_tool)"
+       fi
+       if diff_mode; then
+               echo "$(git config difftool.$merge_tool.cmd ||
+                       git config mergetool.$merge_tool.cmd)"
+       else
+               echo "$(git config mergetool.$merge_tool.cmd)"
+       fi
 }
 
 run_merge_tool () {
+       merge_tool_path="$(get_merge_tool_path "$1")" || exit
        base_present="$2"
        status=0
 
@@ -103,9 +105,9 @@ run_merge_tool () {
                        status=$?
                else
                        ("$merge_tool_path" --auto \
-                        --L1 "$MERGED (A)" \
-                        --L2 "$MERGED (B)" "$LOCAL" "$REMOTE" \
-                        > /dev/null 2>&1)
+                               --L1 "$MERGED (A)" \
+                               --L2 "$MERGED (B)" "$LOCAL" "$REMOTE" \
+                       > /dev/null 2>&1)
                fi
                ;;
        kompare)
@@ -262,6 +264,7 @@ run_merge_tool () {
                fi
                ;;
        *)
+               merge_tool_cmd="$(get_merge_tool_cmd "$1")"
                if test -z "$merge_tool_cmd"; then
                        if merge_mode; then
                                status=1
@@ -269,7 +272,9 @@ run_merge_tool () {
                        break
                fi
                if merge_mode; then
-                       if test "$merge_tool_trust_exit_code" = "false"; then
+                       trust_exit_code="$(git config --bool \
+                               mergetool."$1".trustExitCode || echo false)"
+                       if test "$trust_exit_code" = "false"; then
                                touch "$BACKUP"
                                ( eval $merge_tool_cmd )
                                check_unchanged
@@ -315,64 +320,66 @@ guess_merge_tool () {
        do
                merge_tool_path="$(translate_merge_tool_path "$i")"
                if type "$merge_tool_path" > /dev/null 2>&1; then
-                       merge_tool="$i"
-                       break
+                       echo "$i"
+                       return 0
                fi
        done
 
-       if test -z "$merge_tool" ; then
-               echo >&2 "No known merge resolution program available."
-               return 1
-       fi
-       echo "$merge_tool"
+       echo >&2 "No known merge resolution program available."
+       return 1
 }
 
 get_configured_merge_tool () {
        # Diff mode first tries diff.tool and falls back to merge.tool.
        # Merge mode only checks merge.tool
        if diff_mode; then
-               tool=$(git config diff.tool)
-       fi
-       if test -z "$tool"; then
-               tool=$(git config merge.tool)
+               merge_tool=$(git config diff.tool || git config merge.tool)
+       else
+               merge_tool=$(git config merge.tool)
        fi
        if test -n "$merge_tool" && ! valid_tool "$merge_tool"; then
                echo >&2 "git config option $TOOL_MODE.tool set to unknown tool: $merge_tool"
                echo >&2 "Resetting to default..."
                return 1
        fi
-       echo "$tool"
+       echo "$merge_tool"
 }
 
 get_merge_tool_path () {
        # A merge tool has been set, so verify that it's valid.
+       if test -n "$1"; then
+               merge_tool="$1"
+       else
+               merge_tool="$(get_merge_tool)"
+       fi
        if ! valid_tool "$merge_tool"; then
                echo >&2 "Unknown merge tool $merge_tool"
                exit 1
        fi
        if diff_mode; then
-               merge_tool_path=$(git config difftool."$merge_tool".path)
+               merge_tool_path=$(git config difftool."$merge_tool".path ||
+                                 git config mergetool."$merge_tool".path)
+       else
+               merge_tool_path=$(git config mergetool."$merge_tool".path)
        fi
        if test -z "$merge_tool_path"; then
-               merge_tool_path=$(git config mergetool."$merge_tool".path)
+               merge_tool_path="$(translate_merge_tool_path "$merge_tool")"
        fi
-       merge_tool_path="$(translate_merge_tool_path "$merge_tool" "$merge_tool_path")"
-       if test -z "$merge_tool_cmd" && ! type "$merge_tool_path" > /dev/null 2>&1; then
-               echo >&2 "The $TOOL_MODE tool $merge_tool is not available as '$merge_tool_path'"
+       if test -z "$(get_merge_tool_cmd "$merge_tool")" &&
+       ! type "$merge_tool_path" > /dev/null 2>&1; then
+               echo >&2 "The $TOOL_MODE tool $merge_tool is not available as"\
+                        "'$merge_tool_path'"
                exit 1
        fi
        echo "$merge_tool_path"
 }
 
 get_merge_tool () {
-       merge_tool="$1"
        # Check if a merge tool has been configured
-       if test -z "$merge_tool"; then
-               merge_tool=$(get_configured_merge_tool)
-       fi
+       merge_tool=$(get_configured_merge_tool)
        # Try to guess an appropriate merge tool if no tool has been set.
        if test -z "$merge_tool"; then
-               merge_tool=$(guess_merge_tool) || exit
+               merge_tool="$(guess_merge_tool)" || exit
        fi
        echo "$merge_tool"
 }

diff --git a/git-mergetool.sh b/git-mergetool.sh
index 2e3e02b3b5b45af781fea529e9f3f68fce4a9bd0..b52a7410bcb7b37dce0f4d6213dddedd2c1e42e7 100755 (executable)
--- a/git-mergetool.sh
+++ b/git-mergetool.sh
@@ -174,9 +174,11 @@ merge_file () {
        read ans
     fi
 
-    present=false
-    base_present &&
-    present=true
+    if base_present; then
+           present=true
+    else
+           present=false
+    fi
 
     if ! run_merge_tool "$merge_tool" "$present"; then
        echo "merge of $MERGED failed" 1>&2
@@ -254,12 +256,11 @@ prompt_after_failed_merge() {
     done
 }
 
-merge_tool=$(get_merge_tool "$merge_tool") || exit
-merge_tool_cmd="$(get_merge_tool_cmd "$merge_tool")"
-merge_tool_path="$(get_merge_tool_path "$merge_tool")" || exit
+if test -z "$merge_tool"; then
+    merge_tool=$(get_merge_tool "$merge_tool") || exit
+fi
 merge_keep_backup="$(git config --bool mergetool.keepBackup || echo true)"
 merge_keep_temporaries="$(git config --bool mergetool.keepTemporaries || echo false)"
-merge_tool_trust_exit_code="$(git config --bool mergetool."$merge_tool".trustExitCode || echo false)"
 
 last_status=0
 rollup_status=0