How to see which files are identical given a list of files in two projects

Question

I have two projects named project1 and project2 with identical file trees as follows.

project1/, project2/

.
├── src
│   ├── index.html
│   ├── main.js
│   ├── normalize.js
│   ├── routes
│   │   ├── index.js
│   │   └── Home
│   │       ├── index.js
│   │       └── assets
│   ├── static
│   ├── store
│   │   ├── createStore.js
│   │   └── reducers.js
│   └── styles
└── project.config.js

Now I want to compare to see if the following files from each tree are identical to each other.

files-to-compare.txt

src/main.js
src/routes/index.js
src/store/reducers.js
project.config.js

Is there any way to accomplish this using a single unix command which leverages the list of files-to-compare.txt without having to do a separate command for each file in the list? If so, how?

Edit: This is a different question than this one because that question asks about comparing all the files in two directories. This question asks about specific files sprinkled across multiple directories. Excluding many of those that would have otherwise been included by the answers to the other question.

Answer 1

In a single line -- not a single command -- calling diff once for each:

while IFS= read -r filename; do diff project1/"$filename" project2/"$filename"; done < files-to-compare.txt

This reads the files-to-compare.txt file line-by-line, ensuring that nothing gets in the way of reading the entire line, then calls diff with that filename under each of the project1 and project2 directories.