Script used to build the jest test command from git uncommitted changes

get-test-command.sh

#!/bin/bash

# This script is used to build the jest test command from git uncommitted changes
#
# Usage:
#   get-test-command            # directory-based command (default)
#   get-test-command -e         # explicit file-based command
#   get-test-command --explicit # explicit file-based command
#   get-test-command -r         # run the command instead of just printing it
#   get-test-command --run      # run the command instead of just printing it

# Parse flags
explicit=false
run=false
for arg in "$@"; do
    case "$arg" in
        -e|--explicit)
            explicit=true
            ;;
        -r|--run)
            run=true
            ;;
    esac
done

files=$(git ls-files --modified && git ls-files --others --exclude-standard)

# cmd_args is used to run the command reliably (no copy-paste spacing issues).
cmd_args=(yarn test)

if [ "$explicit" = true ]; then
    # Explicit mode: list each changed file individually.
    # Test/spec files become test targets, and every other changed file is used
    # as a collectCoverageFrom source so coverage is scoped to exactly what changed.
    # for example yarn test helpers/services/appInsights.test.ts --coverage --coverageDirectory='coverage' --collectCoverageFrom='helpers/services/appInsightsClient.ts'
    test_targets=()
    coverage_targets=()

    for file in $files; do
        case "$file" in
            *.test.*|*.spec.*)
                test_targets+=("$file")
                ;;
            *)
                coverage_targets+=("$file")
                ;;
        esac
    done

    cmd_args+=("${test_targets[@]}" --coverage --coverageDirectory=coverage)
    for src in "${coverage_targets[@]}"; do
        cmd_args+=("--collectCoverageFrom=$src")
    done
else
    # Directory mode (default): extract unique directory paths
    dirs=$(echo "$files" | awk -F/ '{OFS="/"; $NF=""; print $0}' | sort -u)

    # Build test command
    # for example yarn test components/test-folder1/ components/test-folder2/  --coverage --coverageDirectory='coverage'  --collectCoverageFrom='components/test-folder1/**/*.*' --collectCoverageFrom='components/test-folder2/**/*.*'
    test_targets=()
    coverage_targets=()

    for dir in $dirs; do
        test_targets+=("$dir")
        coverage_targets+=("${dir}**/*.*")
    done

    cmd_args+=("${test_targets[@]}" --coverage --coverageDirectory=coverage)
    for src in "${coverage_targets[@]}"; do
        cmd_args+=("--collectCoverageFrom=$src")
    done
fi

# Build a copy-paste-friendly string (each argument quoted) for display.
test_command=""
for arg in "${cmd_args[@]}"; do
    case "$arg" in
        --collectCoverageFrom=*)
            test_command="$test_command --collectCoverageFrom='${arg#--collectCoverageFrom=}'"
            ;;
        *)
            test_command="$test_command $arg"
            ;;
    esac
done
test_command="${test_command# }"

# Output the test command
echo "$test_command"

# Optionally run the command.
# yarn (via a version manager) is typically only on PATH in the interactive
# login shell, so run through it to load that environment. printf %q keeps each
# argument safely quoted, immune to spacing issues.
if [ "$run" = true ]; then
    run_cmd=$(printf '%q ' "${cmd_args[@]}")
    exec "${SHELL:-bash}" -ic "$run_cmd"
fi