Visual Studio Code task regex not capturing build error output - regex

Question

I am having some problems with my Regex for parsing build output from rustc.
The output looks like
Compiling svd2rust v0.2.1 (file:///C:/trust/svd2rust)
error: expected one of `=>`, `#`, `if`, or `|`, found `Some`
--> src\main.rs:56:9
|
56 | Some("all") =>
| ^^^^
error: aborting due to previous error
error: Could not compile `svd2rust`.
To learn more, run the command again with --verbose.
My task at the moment looks like:
{
"version": "0.1.0",
"command": "cargo",
"isShellCommand": true,
"args": ["build"],
"problemMatcher": {
"owner": "build",
"fileLocation": ["relative", "${workspaceRoot}"],
"pattern": {
"regexp": "(error):(.*)\\s+-->\\s+(.*):(\\d+):(\\d+)",
"file": 3,
"line": 4,
"column": 5,
"severity": 1,
"message": 2
}
}
}
According to regex101, it looks like the regex should match the appropriate sections.

Answer 1

According to the VS Code documentation, you need a multiline problem matcher. This might work; I did not test it:
{
"version": "0.1.0",
"command": "cargo",
"isShellCommand": true,
"args": ["build"],
"problemMatcher": {
"owner": "build",
"fileLocation": ["relative", "${workspaceRoot}"],
"pattern": [{
"regexp": "(error):(.*)",
"severity": 1,
"message": 2
},{
"regexp": "-->\\s+([^:]*):(\\d+):(\\d+)",
"file": 1,
"line": 2,
"column": 3
}]
}
}

Answer 2

Correct regexp for Rust v1.20.0:
"pattern": [{
"regexp": "(error(?:\\[E\\d{4}\\])?|warning):\\s(.*)",
"severity": 1,
"message": 2
},{
"regexp": "-->\\s+([^:]*):(\\d+):(\\d+)",
"file": 1,
"line": 2,
"column": 3
}]