convert_to_mocha.sh

#!/bin/bash
set -euo pipefail

FILE_PATH="$(realpath $BASH_SOURCE)"
CURRENT_DIR="$(dirname $FILE_PATH)"

cd $CURRENT_DIR;

echo "Removing Jest and it's dependencies"

JEST_PACKAGES=("jest" "jest-junit" "@swc-jest" "ts-jest" "@types/jest" "eslint-plugin-jest" "eslint-plugin-jest-formatting")

for package_name in ${JEST_PACKAGES[@]};
do

	echo "Looking for $package_name in installed dependencies"

	if yarn list --pattern $package_name --depth 0 | grep -q " $package_name@"; then

		echo "Found package $package_name, removing"

		yarn remove --silent $package_name

		echo "Removed package $package_name"
	fi

done

echo "Installing Mocha, Chai, Sinon, chai-as-promised c8 and SWC"
yarn add -D \
	 mocha \
	 chai \
	 sinon \
	 chai-as-promised \
	 c8 \
	 @types/mocha \
	 @types/chai \
	 @types/sinon \
	 @types/chai-as-promised \
	 @swc/core \
	 ts-node

echo "Removing Jest configuration files"
rm -f jest.config.js
rm -f jest.config.cjs
rm -f jest.config.json

echo "Creating .mocharc.json file"
cat > .mocharc.json << EOF
{
  "extension": ["ts"],
  "node-option": ["experimental-specifier-resolution=node", "loader=ts-node/esm"],
  "spec": ["__tests__/**/*.spec.ts"],
  "timeout": 5000,
  "parallel": true,
  "checkLeaks": true,
  "diff": true,
  "forbidPending": true
}

EOF

echo "Creating tsconfig.mocha.json"
cat > tsconfig.mocha.json << EOF
{
  "extends": "./tsconfig.json",
  "include": [".", "./**/.*", "./**/*.json"],
  "ts-node": {
    "files": true,
    "swc": true
  }
}

EOF

echo "Creating .c8rc.json"
cat > .c8rc.json << EOF
{
  "exclude": [],
  "reporter": ["html"],
  "report-dir": "./coverage",
  "skip-full": false,
  "check-coverage": true,
  "statements": 80,
  "branches": 80,
  "functions": 80,
  "lines": 80
}

EOF

echo "Converting all .spec.ts files to Mocha syntax"

FILES=$(find "./__tests__" -name "*.spec.ts")

for path in $FILES
do

    echo "Editing $path"

	echo 'Adding necessary imports and eslint ignore to file'
	echo -e "/* eslint-disable @typescript-eslint/no-unused-expressions */\nimport { expect as chaiExpect, use as chaiUse } from 'chai';\nimport { default as chaiAsPromised } from 'chai-as-promised';\n\n$(cat $path)" > "$path"
	echo -e "$(cat $path)\n/* eslint-enable @typescript-eslint/no-unused-expressions */" > "$path"

    if [[ "$OSTYPE" == "linux-gnu"* ]]; then

		echo 'Registering chaiAsPromised'
		sed -r -i "0,/describe/s//chaiUse(chaiAsPromised);\n\ndescribe/" "$path"

		echo 'Removing expect.assertions() expressions'
        sed -r -i -e "s/expect\.assertions\([0-9]*\);//" "$path"

		echo 'Converting expect statements to chaiExpect'
        sed -r -i -e "s/expect\(/chaiExpect(/" "$path"

		echo 'Converting toBeInstanceOf statements'
		sed -r -i -e "s/\.toBeInstanceOf/.to.be.instanceof/" "$path"

		echo 'Converting toStrictEqual statements'
		sed -r -i -e "s/\.toStrictEqual/.to.deep.equal/" "$path"

		echo 'Converting toBeUndefined statements'
		sed -r -i -e "s/\.toBeUndefined\(\)/.to.be.undefined/" "$path"

		echo 'Converting toBeDefined statements'
		sed -r -i -e "s/\.toBeDefined\(\)/.not.to.be.undefined/" "$path"

		echo 'Converting toBe statements'
		sed -r -i -e "s/\.toBe/.to.equal/" "$path"

		echo 'Converting toMatch statements'
		sed -r -i -e "s/\.toMatch/.to.match/" "$path"

		echo 'Converting toHaveLength statements'
		sed -r -i -e "s/\.toHaveLength/.to.have.lengthOf/" "$path"

		echo 'Converting rejects.toThrow statements'
		sed -r -i -e "s/\.rejects\.toThrow\([^)]*\)/.to.eventually.be.rejected/" "$path"

		echo 'Converting resolves.not.toThrow statements'
		sed -r -i -e "s/\.resolves\.not\.toThrow\([^)]*\)/.to.eventually.not.be.rejected/" "$path"

		echo 'Converting toThrow statements'
		sed -r -i -e "s/\.toThrow\(([^)]*)\)/.to.throw(\1)/" "$path"

		echo 'Converting resolves.to statements'
		sed -r -i -e "s/\.resolves\.to/.to.eventually/" "$path"

		echo 'Converting rejects.to statements'
		sed -r -i -e "s/\.rejects\.to/.to.eventually/" "$path"


    elif [[ "$OSTYPE" == "darwin"* ]]; then

		echo 'Registering chaiAsPromised'
		sed -r -i '' "0,/describe/s//chaiUse(chaiAsPromised);\n\ndescribe/" "$path"

		echo 'Removing expect.assertions() expressions'
        sed -r -i '' "s/expect\.assertions\([0-9]*\);//" "$path"

		echo 'Converting expect statements to chaiExpect'
        sed -r -i '' "s/expect\(/chaiExpect(/" "$path"

		echo 'Converting toBeInstanceOf statements'
		sed -r -i '' "s/\.toBeInstanceOf/.to.be.instanceof/" "$path"

		echo 'Converting toStrictEqual statements'
		sed -r -i '' "s/\.toStrictEqual/.to.deep.equal/" "$path"

		echo 'Converting toBeUndefined statements'
		sed -r -i '' "s/\.toBeUndefined\(\)/.to.be.undefined/" "$path"

		echo 'Converting toBeDefined statements'
		sed -r -i '' "s/\.toBeDefined\(\)/.not.to.be.undefined/" "$path"

		echo 'Converting toBe statements'
		sed -r -i '' "s/\.toBe/.to.equal/" "$path"

		echo 'Converting toMatch statements'
		sed -r -i '' "s/\.toMatch/.to.match/" "$path"

		echo 'Converting toHaveLength statements'
		sed -r -i '' "s/\.toHaveLength/.to.have.lengthOf/" "$path"

		echo 'Converting rejects.toThrow statements'
		sed -r -i '' "s/\.rejects\.toThrow\([^)]*\)/.to.eventually.be.rejected/" "$path"

		echo 'Converting resolves.not.toThrow statements'
		sed -r -i '' "s/\.resolves\.not\.toThrow\([^)]*\)/.to.eventually.not.be.rejected/" "$path"

		echo 'Converting toThrow statements'
		sed -r -i '' "s/\.toThrow\(([^)]*)\)/.to.throw(\1)/" "$path"

		echo 'Converting resolves.to statements'
		sed -r -i '' "s/\.resolves\.to/.to.eventually/" "$path"

		echo 'Converting rejects.to statements'
		sed -r -i '' "s/\.rejects\.to/.to.eventually/" "$path"

    fi

done

echo "Done converting files to Mocha syntax"