harn-lint 0.10.122

use super::*;
use harn_parser::DiagnosticCode as Code;

#[test]
fn test_nil_coalesce_noop_fix_drops_nil_fallback() {
    let source = r"
pipeline default(task) {
  const value = task?.flag ?? nil
  log(value)
}
";
    let diags = lint_source(source);
    assert_eq!(count_rule(&diags, "nil-coalesce-noop"), 1, "{diags:?}");
    let fix = get_fix(&diags, "nil-coalesce-noop").expect("fix");
    assert_eq!(fix.len(), 1);
    assert_eq!(fix[0].replacement, "");

    let result = apply_fixes(source, &diags);
    assert!(
        result.contains("const value = task?.flag\n"),
        "expected nil fallback to be removed, got: {result}"
    );
    let mut lexer = Lexer::new(&result);
    let tokens = lexer.tokenize().expect("relex after fix");
    let mut parser = Parser::new(tokens);
    parser.parse().expect("reparse after fix");
}

#[test]
fn test_nil_coalesce_noop_is_error_by_default() {
    let source = r"
pipeline default(task) {
  const value = task?.flag ?? nil
  log(value)
}
";
    let diags = lint_source(source);
    let diag = diags
        .iter()
        .find(|diag| diag.rule == "nil-coalesce-noop")
        .expect("nil coalesce diag");
    assert_eq!(diag.severity, LintSeverity::Error);
}

#[test]
fn test_nil_coalesce_noop_ignores_real_fallbacks() {
    let source = r#"
pipeline default(task) {
  const value = task?.flag ?? "off"
  log(value)
}
"#;
    let diags = lint_source(source);
    assert!(
        !has_rule(&diags, "nil-coalesce-noop"),
        "non-nil fallback should not trigger: {diags:?}"
    );
}

#[test]
fn test_nil_coalesce_noop_fix_drops_false_from_positive_assert() {
    let source = r#"
pipeline default(task) {
  assert(
    task?.ready
      ?? false,
    "task must be ready",
  )
}
"#;
    let diags = lint_source(source);
    assert_eq!(count_rule(&diags, "nil-coalesce-noop"), 1, "{diags:?}");

    let result = apply_fixes(source, &diags);
    assert!(
        result.contains("task?.ready,"),
        "expected assert to use native truthiness, got: {result}"
    );
    let mut lexer = Lexer::new(&result);
    let tokens = lexer.tokenize().expect("relex after fix");
    let mut parser = Parser::new(tokens);
    parser.parse().expect("reparse after fix");
}

#[test]
fn test_nil_coalesce_noop_preserves_false_outside_exact_positive_assert() {
    let source = r"
pipeline default(task) {
  const stored = task?.ready ?? false
  assert(!(task?.ready ?? false))
  assert((task?.ready ?? false) == true)
  assert(!(task?.ready ?? true))
  log(stored)
}
";
    let diags = lint_source(source);
    assert!(
        !has_rule(&diags, "nil-coalesce-noop"),
        "semantic fallbacks outside an exact positive assertion must remain: {diags:?}"
    );
}

#[test]
fn test_nil_coalesce_noop_preserves_false_for_shadowed_assert() {
    for source in [
        r"
fn assert(value: bool?) -> bool { return true }
pipeline default(task) {
  assert(task?.ready ?? false)
}
",
        r#"
import { assert } from "custom"
pipeline default(task) {
  assert(task?.ready ?? false)
}
"#,
        r#"
import "custom"
pipeline default(task) {
  assert(task?.ready ?? false)
}
"#,
        r"
pipeline default(task) {
  const assert = { value -> true }
  assert(task?.ready ?? false)
}
",
    ] {
        let diags = lint_source(source);
        assert!(
            !has_rule(&diags, "nil-coalesce-noop"),
            "a possibly shadowed assert must not receive a builtin-only fix: {diags:?}"
        );
    }
}

#[test]
fn test_nil_coalesce_self_fallback_fix_drops_identity_fallback() {
    let source = r"
pipeline default(task) {
  const value = task ?? task
  log(value)
}
";
    let diags = lint_source(source);
    assert_eq!(
        count_rule(&diags, "nil-coalesce-self-fallback"),
        1,
        "{diags:?}"
    );
    let diag = diags
        .iter()
        .find(|diag| diag.rule == "nil-coalesce-self-fallback")
        .expect("self fallback diag");
    assert_eq!(diag.severity, LintSeverity::Error);
    assert_eq!(diag.code, Code::LintNilCoalesceSelfFallback);

    let result = apply_fixes(source, &diags);
    assert!(
        result.contains("const value = task\n"),
        "expected self fallback to be removed, got: {result}"
    );
    let mut lexer = Lexer::new(&result);
    let tokens = lexer.tokenize().expect("relex after fix");
    let mut parser = Parser::new(tokens);
    parser.parse().expect("reparse after fix");
}

#[test]
fn test_nil_coalesce_self_fallback_ignores_repeated_effectful_calls() {
    let source = r"
pipeline default(task) {
  const value = load() ?? load()
  log(value)
}
";
    let diags = lint_source(source);
    assert!(
        !has_rule(&diags, "nil-coalesce-self-fallback"),
        "repeated calls may have effects and should not trigger: {diags:?}"
    );
}