Bug: alignColons formatting setting affects semicolon on first line

[xpe]

The alignColons setting, as I understand it, should only impact colons (:). However, I've noticed that it changes the formatting of semicolons (;) on the first line in both my parser grammar and lexer grammar.

For example, here is the result of formatting:

lexer grammar FooLexer
    ;

Just in case there might be some kind of interactions between settings, here are my settings:

    "antlr4.format": {
        "alignTrailingComments": true,
        "allowShortBlocksOnASingleLine": true,
        "breakBeforeBraces": false,
        "columnLimit": 78,
        "continuationIndentWidth": 4,
        "indentWidth": 4,
        "keepEmptyLinesAtTheStartOfBlocks": false,
        "maxEmptyLinesToKeep": 1,
        "reflowComments": false,
        "spaceBeforeAssignmentOperators": true,
        "tabWidth": 4,
        "useTab": false,
        "alignColons": "hanging",
        "singleLineOverrulesHangingColon": true,
        "allowShortRulesOnASingleLine": true,
        "alignSemicolons": "hanging",
        "breakBeforeParens": false,
        "ruleInternalsOnSingleLine": false,
        "minEmptyLines": 1,
        "groupedAlignments": true,
        "alignFirstTokens": true,
        "alignLexerCommands": false,
        "alignActions": false,
        "alignLabels": true,
        "alignTrailers": false
    },

[mike-lischke]

You have set "alignSemicolons" to hanging as well. This is probably why you got this result.

[xpe]

You have set "alignSemicolons" to hanging as well. This is probably why you got this result.

Do you agree with these statements:

• alignSemicolons should only apply to rule definitions.
• alignSemicolons should not apply to the first line of a grammar file (e.g. grammar, lexer grammar, or parser grammar).

[xpe]

My goal is setup the extension to do ANTLR formatting along the lines of common examples provided in TDAR and many examples in the ANTLR4 grammars repo. This means:

• in rules, align :, |, and ;
• use semicolons normally in non-rules (such as lexer grammar FooGrammar;)

I don't think this is currently possible given the current setting options, which is why I filed this as a bug.

[mike-lischke]

Do you agree with these statements:

* `alignSemicolons` should _only_ apply to rule definitions.

* `alignSemicolons` should _not_ apply to the first line of a grammar file (e.g. `grammar`, `lexer grammar`, or `parser grammar`).

I haven't thought about other occurences than rules, so I cannot answer with yes currently. However, I have not seen output where the semicolon from the introducer line is placed on the next line and I have tests with all 3 semicolon settings. But maybe I just missed that.

[mike-lischke]

My goal is setup the extension to do ANTLR formatting along the lines of common examples provided in TDAR and many examples in the ANTLR4 grammars repo. This means:

* in rules, align `:`, `|`, and `;`

* use semicolons normally in non-rules (such as `lexer grammar FooGrammar;`)

I agree. The setting should not affect non-rules.

I don't think this is currently possible given the current setting options, which is why I filed this as a bug.

If that's the case then it should be fixed. Interesting here is that I never got a bug report for this issue, which either means people don't care about it or they never use hanging semicolons. I certainly do not.