Scaffold TCA Feature in Tuist Project script

scaffold_tca_feature.sh

#!/bin/bash
set -e

# This script does the following, for a given ComposableArchitecture feature.
# Suppose we are running `./Scripts/scaffold_tca_feature.sh LoginFeature` as an example.
# 
# - Create intermediate folders and boilerplate files for 4 targets: 
#   LoginFeatureKit, LoginFeatureUI, LoginFeatureKitTests, LoginFeatureUITests
# - Create a Tuist manifest file representing the targets at:
#   ./Tuist/ProjectDescriptionHelpers/Targets/Features/LoginFeature.swift
# - Insert the new targets into Tuist’s `Project.swift`, maintaining an alphabetical array of targets.
# - Commit the changes and regenerate the project.
#
# A bunch of aspects of this script are opinionated based on my own infrastructure.
# For example, a `CFTargetGroup` is an abstraction bundling a bunch of `ProjectDescription.Target`s.
# Therefore, don’t expect to just "drop in" this script to your project - it is
# posted as a gist only as a reference/inspiration to others using Tuist as a way to improve automation and velocity.

NEW_FEATURE_NAME=$1

if [[ -z "$NEW_FEATURE_NAME" ]]; then
  echo "No feature name provided. Provide a feature name, capitalized, like: './Scripts/scaffold_tca_feature.sh MyNewFeature'"
  exit 1
fi

echo "Scaffolding ${NEW_FEATURE_NAME}Kit target."
mkdir -p "Targets/Features/${NEW_FEATURE_NAME}Kit/Sources"
cat <<EOF > "Targets/Features/${NEW_FEATURE_NAME}Kit/Sources/${NEW_FEATURE_NAME}.swift"
import ComposableArchitecture

@Reducer public struct $NEW_FEATURE_NAME {
    @ObservableState public struct State {
        public init() { }
    }
    public init() { }
}
EOF

echo "Scaffolding ${NEW_FEATURE_NAME}UI target."
mkdir -p "Targets/Features/${NEW_FEATURE_NAME}UI/Sources"
cat <<EOF > "Targets/Features/${NEW_FEATURE_NAME}UI/Sources/${NEW_FEATURE_NAME}View.swift"
import ComposableArchitecture
import ${NEW_FEATURE_NAME}Kit
import SwiftUI

public struct ${NEW_FEATURE_NAME}View: View {
    @Bindable var store: StoreOf<${NEW_FEATURE_NAME}>

    public init(store: StoreOf<${NEW_FEATURE_NAME}>) {
        self.store = store
    }

    public var body: some View {
        Text("Hello, world!")
    }
}
EOF

echo "Scaffolding (empty) test targets."
mkdir -p "Targets/Features/${NEW_FEATURE_NAME}Kit/Tests"
touch "Targets/Features/${NEW_FEATURE_NAME}Kit/Tests/${NEW_FEATURE_NAME}Tests.swift"
mkdir -p "Targets/Features/${NEW_FEATURE_NAME}UI/Tests"
touch "Targets/Features/${NEW_FEATURE_NAME}UI/Tests/${NEW_FEATURE_NAME}ViewTests.swift"

echo "Scaffolding Tuist manifest file."
TUIST_FILE="Tuist/ProjectDescriptionHelpers/Targets/Features/${NEW_FEATURE_NAME}.swift"
lowercase_first_letter() {
    input="$1"
    echo "$(tr '[:upper:]' '[:lower:]' <<< "${input:0:1}")${input:1}"
}
NEW_FEATURE_NAME_LOWER=$(lowercase_first_letter "$NEW_FEATURE_NAME")

cat <<EOF > $TUIST_FILE
import CFTuist

public extension CFTargetGroup {
    static let ${NEW_FEATURE_NAME_LOWER} = Self.projectDefault.feature(
        kitTarget: .init(
            name: .${NEW_FEATURE_NAME_LOWER}Kit
        ),
        uiTarget: .init(
            name: .${NEW_FEATURE_NAME_LOWER}UI
        )
    )
}

public extension CFTargetDependency {
    static let ${NEW_FEATURE_NAME_LOWER}Kit: Self = .target(.${NEW_FEATURE_NAME_LOWER}Kit)
    static let ${NEW_FEATURE_NAME_LOWER}UI: Self = .target(.${NEW_FEATURE_NAME_LOWER}UI)
}
public extension CFTarget.Name {
    static let ${NEW_FEATURE_NAME_LOWER}Kit: Self = "${NEW_FEATURE_NAME}Kit"
    static let ${NEW_FEATURE_NAME_LOWER}UI: Self = "${NEW_FEATURE_NAME}UI"
}
EOF

echo "Adding new target group .${NEW_FEATURE_NAME_LOWER} to Tuist Project.swift file."

# File to modify
FILE="Project.swift"

# Find the line number where 'targetGroups: [' starts
START_LINE=$(grep -n 'targetGroups: \[' "$FILE" | cut -d: -f1)

if [ -z "$START_LINE" ]; then
  echo "Error: 'targetGroups: [' not found in $FILE"
  exit 1
fi

# Find the line number where the 'targetGroups' array ends
END_LINE=$(awk "NR>$START_LINE-1 && /],/ {print NR; exit}" "$FILE")

if [ -z "$END_LINE" ]; then
  echo "Error: Closing bracket for 'targetGroups' not found."
  exit 1
fi

# Extract the existing items
sed -n "${START_LINE},${END_LINE}p" "$FILE" | sed '1d;$d' | sed 's/^[[:space:]]*\.//;s/,$//' > tmp_targetGroups.txt

# Add the new item
echo "$NEW_FEATURE_NAME_LOWER" | sed 's/^[[:space:]]*\.//' >> tmp_targetGroups.txt

# Sort the items alphabetically
SORTED_ITEMS=$(sort tmp_targetGroups.txt)

# Reconstruct the 'targetGroups' section
{
  sed -n "1,$((START_LINE - 1))p" "$FILE"
  echo "    targetGroups: ["
  echo "$SORTED_ITEMS" | sed 's/^/        ./' | sed 's/$/,/'
  echo "    ],"
  sed -n "$((END_LINE + 1)),\$p" "$FILE"
} > "$FILE.tmp" && mv "$FILE.tmp" "$FILE"

# Clean up
rm tmp_targetGroups.txt
echo "Successfully added .$NEW_FEATURE_NAME_LOWER to Tuist Project.swift file."

echo "Committing changes."
git add . && git commit -m "Scaffold ${NEW_FEATURE_NAME}"

echo "Done scaffolding! Regenerating the project."
tuist generate