Feature Request: report incorrect or malformed values in library.properties

[ianfixes]

Feature Request

Create what is essentially a linting tool for library.properties. This would catch things like the following:

• the library.properties filename is capitalized in an unexpected way (if case-sensitive filesystems would care)
• the file contains binary, or has some other text encoding error
• the file contains unexpected keys
• a key contains an unparseable value
• an expected key was not found

Example JSON output

{
  "file": {
    "path": "/path/to/Library.PROPerties",
    "issues": [
      {
        "severity": "warning",
        "message": "The library.properties filename should be all lowercase"
      },
      {
        "severity": "error",
        "message": "File contains binary data"
       }
    ]
  },
  "contents": {
    "parsed": {
        /* the parsed contents of the file */
    },
    "issues": [
      {
        "severity": "warning",
        "message": "The 'name' field was not found"
      },
      {
        "severity": "warning",
        "message": "Unexpected field 'potatoes'",
        "line": 4
      },
      {
        "severity": "error",
        "message": "field 'dot_a_linkage' expects a boolean",
        "line": 8
      },
    ]
  }
}

Having the line number reported in the output would enable GitHub annotations directly on the affected lines.

[per1234]

Thanks @ianfixes. As you noticed, we have now released the Arduino Lint tool which provides this capability and more:
https://blog.arduino.cc/2021/01/13/detect-problems-with-your-arduino-projects/

The only exception is this:

the file contains unexpected keys

The presence of arbitrary keys in library.properties doesn't cause any problems. People might use these for their own purposes. For example, some library authors began adding a license field even though this is not mentioned in the specification. What we do have is a check for potentially misspelled versions of optional key names (e.g., an architecture key when no architectures key is present).

As part of the Arduino Lint project, the library.properties data format is now defined in a machine readable form as a JSON schema:
https://github.com/arduino/arduino-lint/tree/main/etc/schemas