shrimp/src/parser/tests/control-flow.test.ts

import { expect, describe, test } from 'bun:test'

import '../shrimp.grammar' // Importing this so changes cause it to retest!

describe('if/else if/else', () => {
  test('parses single line if', () => {
    expect(`if y == 1: 'cool' end`).toMatchTree(`
      IfExpr
        keyword if
        ConditionalOp
          Identifier y
          EqEq ==
          Number 1
        colon :
        Block
          String
            StringFragment cool
        keyword end
    `)

    expect('a = if x: 2 end').toMatchTree(`
      Assign
        AssignableIdentifier a
        Eq =
        IfExpr
          keyword if
          FunctionCallOrIdentifier
            Identifier x
          colon :
          Block
            Number 2
          keyword end
    `)
  })

  test('parses multiline if', () => {
    expect(`
    if x < 9:
      yes
    end`).toMatchTree(`
      IfExpr
        keyword if
        ConditionalOp
          Identifier x
          Lt <
          Number 9
        colon :
        Block
          FunctionCallOrIdentifier
            Identifier yes
        keyword end
    `)
  })

  test('parses multiline if with else', () => {
    expect(`if with-else:
      x
    else:
      y
    end`).toMatchTree(`
      IfExpr
        keyword if
        FunctionCallOrIdentifier
          Identifier with-else
        colon :
        Block
          FunctionCallOrIdentifier
            Identifier x
        ElseExpr
          keyword else
          colon :
          Block
            FunctionCallOrIdentifier
              Identifier y
        keyword end
    `)
  })

  test('parses multiline if with else if', () => {
    expect(`if with-else-if:
      x
    else if another-condition:
      y
    end`).toMatchTree(`
      IfExpr
        keyword if
        FunctionCallOrIdentifier
          Identifier with-else-if
        colon :
        Block
          FunctionCallOrIdentifier
            Identifier x
        ElseIfExpr
          keyword else
          keyword if
          FunctionCallOrIdentifier
            Identifier another-condition
          colon :
          Block
            FunctionCallOrIdentifier
              Identifier y
        keyword end
    `)
  })

  test('parses multiline if with multiple else if and else', () => {
    expect(`if with-else-if-else:
      x
    else if another-condition:
      y
    else if yet-another-condition:
      z
    else:
      oh-no
    end`).toMatchTree(`
      IfExpr
        keyword if
        FunctionCallOrIdentifier
          Identifier with-else-if-else
        colon :
        Block
          FunctionCallOrIdentifier
            Identifier x
        ElseIfExpr
          keyword else
          keyword if
          FunctionCallOrIdentifier
            Identifier another-condition
          colon :
          Block
            FunctionCallOrIdentifier
              Identifier y
        ElseIfExpr
          keyword else
          keyword if
          FunctionCallOrIdentifier
            Identifier yet-another-condition
          colon :
          Block
            FunctionCallOrIdentifier
              Identifier z
        ElseExpr
          keyword else
          colon :
          Block
            FunctionCallOrIdentifier
              Identifier oh-no
        keyword end
    `)
  })

  test('does not parse identifiers that start with if', () => {
    expect('iffy = if true: 2 end').toMatchTree(`
      Assign
        AssignableIdentifier iffy
        Eq =
        IfExpr
          keyword if
          Boolean true
          colon :
          Block
            Number 2
          keyword end
    `)
  })

  test('parses function calls in if tests', () => {
    expect(`if var? 'abc': true end`).toMatchTree(`
      IfExpr
        keyword if
        FunctionCall
          Identifier var?
          PositionalArg
            String
              StringFragment abc
        colon :
        Block
          Boolean true
        keyword end
    `)
  })

  test("parses paren'd function calls in if tests", () => {
    expect(`if (var? 'abc'): true end`).toMatchTree(`
      IfExpr
        keyword if
        ParenExpr
          FunctionCall
            Identifier var?
            PositionalArg
              String
                StringFragment abc
        colon :
        Block
          Boolean true
        keyword end
    `)
  })


  test('parses function calls in else-if tests', () => {
    expect(`if false: true else if var? 'abc': true end`).toMatchTree(`
      IfExpr
        keyword if
        Boolean false
        colon :
        Block
          Boolean true
        ElseIfExpr
          keyword else
          keyword if
          FunctionCall
            Identifier var?
            PositionalArg
              String
                StringFragment abc
          colon :
          Block
            Boolean true
        keyword end
    `)
  })

  test("parses paren'd function calls in else-if tests", () => {
    expect(`if false: true else if (var? 'abc'): true end`).toMatchTree(`
      IfExpr
        keyword if
        Boolean false
        colon :
        Block
          Boolean true
        ElseIfExpr
          keyword else
          keyword if
          ParenExpr
            FunctionCall
              Identifier var?
              PositionalArg
                String
                  StringFragment abc
          colon :
          Block
            Boolean true
        keyword end
    `)
  })

  test('allows if/else in parens', () => {
    expect(`eh? = (if true: true end)`).toMatchTree(`
      Assign
        AssignableIdentifier eh?
        Eq =
        ParenExpr
          IfExpr
            keyword if
            Boolean true
            colon :
            Block
              Boolean true
            keyword end
    `)
  })
})

describe('while', () => {
  test('infinite loop', () => {
    expect(`while true: true end`).toMatchTree(`
  WhileExpr
    keyword while
    Boolean true
    colon :
    Block
      Boolean true
    keyword end`)
  })

  test('basic expression', () => {
    expect(`while a > 0: true end`).toMatchTree(`
  WhileExpr
    keyword while
    ConditionalOp
      Identifier a
      Gt >
      Number 0
    colon :
    Block
      Boolean true
    keyword end`)
  })


  test('compound expression', () => {
    expect(`while a > 0 and b < 100 and c < 1000: true end`).toMatchTree(`
  WhileExpr
    keyword while
    ConditionalOp
      ConditionalOp
        ConditionalOp
          Identifier a
          Gt >
          Number 0
        And and
        ConditionalOp
          Identifier b
          Lt <
          Number 100
      And and
      ConditionalOp
        Identifier c
        Lt <
        Number 1000
    colon :
    Block
      Boolean true
    keyword end`)
  })

  test('multiline infinite loop', () => {
    expect(`
      while true: 
        true 
      end`).toMatchTree(`
  WhileExpr
    keyword while
    Boolean true
    colon :
    Block
      Boolean true
    keyword end`)
  })

  test('multiline basic expression', () => {
    expect(`
      while a > 0: 
        true
      end`).toMatchTree(`
  WhileExpr
    keyword while
    ConditionalOp
      Identifier a
      Gt >
      Number 0
    colon :
    Block
      Boolean true
    keyword end`)
  })


  test('multiline compound expression', () => {
    expect(`
      while a > 0 and b < 100 and c < 1000: 
        true 
      end`).toMatchTree(`
  WhileExpr
    keyword while
    ConditionalOp
      ConditionalOp
        ConditionalOp
          Identifier a
          Gt >
          Number 0
        And and
        ConditionalOp
          Identifier b
          Lt <
          Number 100
      And and
      ConditionalOp
        Identifier c
        Lt <
        Number 1000
    colon :
    Block
      Boolean true
    keyword end`)
  })
})