create-patch.sh

#!/usr/bin/env bash
# Git patch creation tool
# v1.0
# (c) Copyright 2023 Adobe Commerce.

# 1. Check required system tools

_check_installed_tools() {
    local tools=("git" "awk" "grep" "head" "pwd" "cat" "dirname" "basename")
    for tool in "${tools[@]}"; do
        if ! command -v "$tool" >/dev/null 2>&1; then
            printf "ERROR: '%s' command is not found. Please install it to proceed.\n" "$tool"
            exit 1
        fi
    done
}

_check_installed_tools

# Determine bin path for system tools
git_bin=$(command -v git)
awk_bin=$(command -v awk)
grep_bin=$(command -v grep)
head_bin=$(command -v head)
pwd_bin=$(command -v pwd)
cat_bin=$(command -v cat)
dirname_bin=$(command -v dirname)
basename_bin=$(command -v basename)

base_name=$($basename_bin "$0")

# 2. Load env variables

tool_dir=$($dirname_bin "$0")
env_file_path="$tool_dir"/.env
if [[ -f "$env_file_path" ]]; then
    source "$env_file_path"
    echo "Loaded .env from $env_file_path."
else
    echo -e "$env_file_path was not found. Copy .env.example to .env and specify the path to the converter tool."
fi

# 3. Help menu

if [[ "$1" == "-?" || "$1" == "-h" || "$1" == "--help" ]]; then
    "$cat_bin" <<EOFH
Usage: sh $base_name [--help] [-b <branch>] [-r <release version>] [-v <version>] [-c <commit>:<commit>]
Generate a patch by collecting changes from the latest tag to HEAD (by default).
The tool should be run from the directory containing the repository.

-b <branch>             Specify the branch. Example: ABCD-1234.

-r <release version>    [Optional] Specify the release version to use for the patch file name.
                        If not specified, the tool will use the latest tag to identify the release version.

-v <patch version>      Specify the patch version. Examples: v2, v3. Omit for v1.

-c <commit>:<commit>    [Optional] Generate a patch by using the changes between two arbitrary <commit>.
                        The patch will be generated by the "git diff" tool.
                        It will be treated the same way as the "git diff" command, for example,
                        if <commit> is omitted on one side, it will have the same effect as using HEAD instead.
                        If this option is omitted, the patch will be generated using the changes from the latest tag to HEAD.

--help                  Show this help message.
EOFH
    exit 0
fi

# 4. Get options

branch=""
release_version=""
patch_version=""
collect_revisions_range=""
while getopts b:v:r:c: opt; do
    case $opt in
    b)
        branch="$OPTARG"
        ;;
    r)
        release_version="$OPTARG"
        ;;
    v)
        patch_version="$OPTARG"
        ;;
    c)
        collect_revisions_range="$OPTARG"
        ;;
    *)
        printf "ERROR: Invalid option: -%s\n" "$OPTARG" >&2
        exit 1
        ;;
    esac
done

# 5. Git preparations

_check_git_revision() {
    local commit="$1"
    if ! git rev-parse --quiet --verify "$commit" >/dev/null 2>&1; then
        printf "ERROR: Invalid revision '%s'.\n" "$commit"
        exit 1
    fi
}

# Determine if the current directory is under git control
is_under_git_control=777
"$git_bin" rev-parse -q >/dev/null 2>&1
is_under_git_control=$?
if [[ ! "$is_under_git_control" -eq 0 ]]; then
    printf "ERROR: The patch can't be created because the current directory is not a Git repository.\n"
    exit 1
fi

# Checkout branch
if [ -n "$branch" ]; then
    $git_bin fetch
    # Check for uncommitted changes
    if ! $git_bin diff --quiet; then
        printf "ERROR: There are uncommitted changes. Please commit or stash them before switching branches.\n"
        exit 1
    fi
    # Attempt to checkout the branch
    if ! $git_bin checkout "$branch" >/dev/null 2>&1; then
        printf "ERROR: The branch '%s' does not exist.\n" "$branch"
        exit 1
    fi
    $git_bin merge
fi

# Get the latest tag in the current branch
current_tag=$($git_bin describe --abbrev=0 --tags)

# If revisions range was omitted, then set the range from the current tag to HEAD
if [ -z "$collect_revisions_range" ]; then
    collect_revisions_range="$current_tag..HEAD"
    start_commit=$($git_bin rev-list "$current_tag" | $head_bin -n 1)
else
    start_commit=$($awk_bin -F ":" '{print $1}' <<<"$collect_revisions_range")
    end_commit=$($awk_bin -F ":" '{print $2}' <<<"$collect_revisions_range")

    # Check if specified "start" and "end" commits exist
    _check_git_revision "$start_commit"

    # If "end" commit was specified (not empty), set the revisions range in the applicable format for "git diff" command
    if [ ! -z "$end_commit" ]; then
        _check_git_revision "$end_commit"
        collect_revisions_range="$start_commit..$end_commit"
    fi

fi

echo "======== Commits in the patch: ========"
"$git_bin" log --oneline --format='%C(auto)%h %Cgreen%ad%Creset %s%C(auto)%d' --color --decorate --date=iso -50 "$collect_revisions_range"
echo "======== Based on: ===================="
"$git_bin" log --oneline --format='%C(auto)%h %Cgreen%ad%Creset %s%C(auto)%d' --color --decorate --date=iso -1 "$("$git_bin" rev-parse "$start_commit")"
echo "======================================="

# 6. Patch tool file name

current_branch=$($git_bin rev-parse --abbrev-ref HEAD)
ticket_number=$(echo "$current_branch" | $grep_bin -oE '^[A-Z]*-[0-9]*')
debug_suffix=$(echo "$current_branch" | $grep_bin -i 'debug')
custom_suffix=$(echo "$current_branch" | $grep_bin -i 'custom')
if [ -n "$debug_suffix" ]; then
    patch_id="${ticket_number}_DEBUG"
else
    patch_id="$ticket_number"
fi
if [ -n "$custom_suffix" ]; then
    patch_id="${patch_id}_CUSTOM"
fi

if [ -z "$release_version" ]; then
    release_version=$($awk_bin '{gsub("v",""); print}' <<<"$current_tag")
fi

if [[ "$patch_version" == "v1" ]] || [[ -z "$patch_version" ]]; then
    patch_version_suffix=
else
    patch_version_suffix="_$patch_version"
fi

patch_file_name_git="${patch_id}_${release_version}${patch_version_suffix}.git.patch"
patch_file_name_composer="${patch_id}_${release_version}${patch_version_suffix}.patch"

# 7. Create the patch file

if ! $git_bin diff -a -p --no-renames "$collect_revisions_range" >"$patch_file_name_git"; then
    echo "Error: Failed to create a git patch file."
    exit 1
fi

# Create a composer version of the file
current_dir=$($pwd_bin)
patch_file_path_git="$current_dir/$patch_file_name_git"
patch_file_path_composer="$current_dir/$patch_file_name_composer"
if [ -n "$PATCH_CONVERTER_TOOL_BIN" ]; then
    $PATCH_CONVERTER_TOOL_BIN "$patch_file_path_git" >"$patch_file_path_composer"
fi

# 8. Report results

if [ -f "$patch_file_path_git" ] && [ "$(wc -c <"$patch_file_path_git")" -gt 1 ]; then
    echo "Git patch created successfully."
    echo "The location of the git patch is: $patch_file_path_git"
else
    echo "Something went wrong while generating the patch."
fi
if [ -f "$patch_file_path_composer" ] && [ "$(wc -c <"$patch_file_path_composer")" -gt 1 ]; then
    echo -e "\e[32mComposer patch created successfully.\e[0m"
    echo "The location of the composer patch is: $patch_file_path_composer"
else
    echo "There was an error while generating the composer patch. Please recheck the converter tool location."
fi
exit 0