This is my solution for the Metric-Imperial Converter freeCodeCamp challenge.

Build a full stack JavaScript app that is functionally similar to the sample project. Working on this project will involve you writing your code using one of the following methods:

• Clone this project's GitHub repo and complete your project locally.
• Use our Replit starter project to complete your project.
• Use a site builder of your choice to complete the project. Be sure to incorporate all the files from our GitHub repo.
• When you are done, make sure a working demo of your project is hosted somewhere public.
• Then submit the URL to it in the Solution Link field. Optionally, also submit a link to your project's source code in the GitHub Link field.

• Complete the necessary conversion logic in /controllers/convertHandler.js
• Complete the necessary routes in /routes/api.js
• Copy the sample.env file to .env and set the variables appropriately
• To run the tests uncomment NODE_ENV=test in your .env file
• To run the tests in the console, use the command npm run test. To open the Replit console, press Ctrl+Shift+P (Cmd if on a Mac) and type "open shell"

Write the following tests in tests/1_unit-tests.js:

• convertHandler should correctly read a whole number input.
• convertHandler should correctly read a decimal number input.
• convertHandler should correctly read a fractional input.
• convertHandler should correctly read a fractional input with a decimal.
• convertHandler should correctly return an error on a double-fraction (i.e. 3/2/3).
• convertHandler should correctly default to a numerical input of 1 when no numerical input is provided.
• convertHandler should correctly read each valid input unit.
• convertHandler should correctly return an error for an invalid input unit.
• convertHandler should return the correct return unit for each valid input unit.
• convertHandler should correctly return the spelled-out string unit for each valid input unit.
• convertHandler should correctly convert gal to L.
• convertHandler should correctly convert L to gal.
• convertHandler should correctly convert mi to km.
• convertHandler should correctly convert km to mi.
• convertHandler should correctly convert lbs to kg.
• convertHandler should correctly convert kg to lbs.

Write the following tests in tests/2_functional-tests.js:

• Convert a valid input such as 10L: GET request to /api/convert.
• Convert an invalid input such as 32g: GET request to /api/convert.
• Convert an invalid number such as 3/7.2/4kg: GET request to /api/convert.
• Convert an invalid number AND unit such as 3/7.2/4kilomegagram: GET request to /api/convert.
• Convert with no number such as kg: GET request to /api/convert.

MIT