Support standard ` --ignore-matching-lines` parameter about difftastic

[Wilfred]

This isn't possible I'm afraid. --ignore-matchine-lines isn't passed to the external diff tool as far as I can see.

$ GIT_PAGER=cat DFT_LOG=trace GIT_EXTERNAL_DIFF=difft git diff --ignore-matching-lines 'app.kubernetes.io/version' --ext-diff
 2024-01-28T20:32:00.303Z INFO  difft::options > CLI arguments: ["src/conflicts.rs", "/tmp/git-blob-BI9V7X/conflicts.rs", "46602124597b3c0c7a20e89beee2a34ce9d376e1", "100644", "src/conflicts.rs", "0000000000000000000000000000000000000000", "100644"]

$ GIT_PAGER=cat DFT_LOG=trace GIT_EXTERNAL_DIFF=difft git diff --ext-diff                    
 2024-01-28T20:32:55.768Z INFO  difft::options > CLI arguments: ["src/conflicts.rs", "/tmp/git-blob-zpaXEJ/conflicts.rs", "46602124597b3c0c7a20e89beee2a34ce9d376e1", "100644", "src/conflicts.rs", "0000000000000000000000000000000000000000", "100644"]

Even if it was possible, I don't see how this feature could work for difftastic. Difftastic is diffing an abstract syntax tree (AST), and there's no way to apply a line-based exclude regex to an AST.

[davinkevin]

Thank you for your answer @Wilfred

This isn't possible I'm afraid. --ignore-matchine-lines isn't passed to the external diff tool as far as I can see.

Maybe something to report to the git project if you think it should be passed to the external diff tool, no?

Difftastic is diffing an abstract syntax tree (AST), and there's no way to apply a line-based exclude regex to an AST

I worked on AST for Java & Kotlin annotation processor, it was possible to filter out some cases when we had the AST representation. I don't want to presume about complexity of difftastic, but a pre or post processing of the value could be possible, if not using the AST directly?

[0xdevalias]

there's no way to apply a line-based exclude regex to an AST

Would it be possible to apply the line-based exclude after the AST-diffing occurs, when it is rendered back to a text format?