// Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.

mod multiple_packages;

use std::{rc::Rc, sync::Arc};

use super::{compile, longest_common_prefix, CompileUnit, Error, PackageStore, SourceMap};
use crate::compile::TargetCapabilityFlags;

use expect_test::expect;
use indoc::indoc;
use miette::Diagnostic;
use qsc_data_structures::{language_features::LanguageFeatures, span::Span};
use qsc_hir::{
    global,
    hir::{
        Block, Expr, ExprKind, ItemId, ItemKind, Lit, LocalItemId, NodeId, Res, SpecBody, Stmt,
        StmtKind,
    },
    mut_visit::MutVisitor,
    ty::{Prim, Ty},
};

fn error_span(error: &Error) -> Span {
    let label = error
        .labels()
        .and_then(|mut ls| ls.next())
        .expect("error should have at least one label");

    let span = label.inner();
    let offset = span
        .offset()
        .try_into()
        .expect("span offset should fit into u32");
    let len: u32 = span.len().try_into().expect("span len should fit into u32");
    Span {
        lo: offset,
        hi: offset + len,
    }
}

fn source_span<'a>(sources: &'a SourceMap, error: &Error) -> (&'a str, Span) {
    let span = error_span(error);
    let source = sources
        .find_by_offset(span.lo)
        .expect("offset should match at least one source");
    (
        &source.name,
        Span {
            lo: span.lo - source.offset,
            hi: span.hi - source.offset,
        },
    )
}

/// runs a compile with the default configuration
fn default_compile(sources: SourceMap) -> CompileUnit {
    compile(
        &PackageStore::new(super::core()),
        &[],
        sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    )
}

#[test]
fn one_file_no_entry() {
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    function A() : Unit {}
                }
            "}
            .into(),
        )],
        None,
    );

    let unit = default_compile(sources);
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);

    let entry = unit.package.entry.as_ref();
    assert!(entry.is_none(), "{entry:#?}");
}

#[test]
fn one_file_error() {
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    function A() : Unit {
                        x
                    }
                }
            "}
            .into(),
        )],
        None,
    );

    let unit = default_compile(sources);
    let errors: Vec<_> = unit
        .errors
        .iter()
        .map(|error| source_span(&unit.sources, error))
        .collect();

    assert_eq!(vec![("test", Span { lo: 50, hi: 51 })], errors);
}

#[test]
fn two_files_dependency() {
    let sources = SourceMap::new(
        [
            (
                "test1".into(),
                indoc! {"
                    namespace Foo {
                        function A() : Unit {}
                    }
                "}
                .into(),
            ),
            (
                "test2".into(),
                indoc! {"
                    namespace Foo {
                        function B() : Unit {
                            A();
                        }
                    }
                "}
                .into(),
            ),
        ],
        None,
    );

    let unit = default_compile(sources);
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);
}

#[test]
fn two_files_mutual_dependency() {
    let sources = SourceMap::new(
        [
            (
                "test1".into(),
                indoc! {"
                    namespace Foo {
                        function A() : Unit {
                            B();
                        }
                    }
                "}
                .into(),
            ),
            (
                "test2".into(),
                indoc! {"
                    namespace Foo {
                        function B() : Unit {
                            A();
                        }
                    }
                "}
                .into(),
            ),
        ],
        None,
    );

    let unit = default_compile(sources);
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);
}

#[test]
fn two_files_error() {
    let sources = SourceMap::new(
        [
            (
                "test1".into(),
                indoc! {"
                    namespace Foo {
                        function A() : Unit {}
                    }
                "}
                .into(),
            ),
            (
                "test2".into(),
                indoc! {"
                    namespace Foo {
                        function B() : Unit {
                            C();
                        }
                    }
                "}
                .into(),
            ),
        ],
        None,
    );

    let unit = default_compile(sources);
    let errors: Vec<_> = unit
        .errors
        .iter()
        .map(|error| source_span(&unit.sources, error))
        .collect();

    assert_eq!(
        vec![
            ("test2", Span { lo: 50, hi: 51 }),
            ("test2", Span { lo: 50, hi: 53 }),
        ],
        errors
    );
}

#[test]
fn entry_call_operation() {
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    operation A() : Unit {}
                }
            "}
            .into(),
        )],
        Some("Foo.A()".into()),
    );

    let unit = default_compile(sources);
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);

    let entry = &unit.package.entry.expect("package should have entry");
    let ExprKind::Call(callee, _) = &entry.kind else {
        panic!("entry should be a call")
    };
    let ExprKind::Var(res, _) = &callee.kind else {
        panic!("callee should be a variable")
    };
    assert_eq!(
        &Res::Item(ItemId {
            package: None,
            item: LocalItemId::from(1),
        }),
        res
    );
}

#[test]
fn entry_error() {
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    operation A() : Unit {}
                }
            "}
            .into(),
        )],
        Some("Foo.B()".into()),
    );

    let unit = default_compile(sources);
    assert_eq!(
        ("<entry>", Span { lo: 0, hi: 5 }),
        source_span(&unit.sources, &unit.errors[0])
    );
}

#[test]
fn replace_node() {
    struct Replacer;

    impl MutVisitor for Replacer {
        fn visit_expr(&mut self, expr: &mut Expr) {
            *expr = Expr {
                id: NodeId::default(),
                span: expr.span,
                ty: Ty::Prim(Prim::Int),
                kind: ExprKind::Lit(Lit::Int(2)),
            };
        }
    }

    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace A {
                    function Foo() : Int {
                        1
                    }
                }
            "}
            .into(),
        )],
        None,
    );

    let mut unit = default_compile(sources);
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);
    Replacer.visit_package(&mut unit.package);
    unit.assigner.visit_package(&mut unit.package);

    let ItemKind::Callable(callable) = &unit
        .package
        .items
        .get(LocalItemId::from(1))
        .expect("package should have item")
        .kind
    else {
        panic!("item should be a callable");
    };
    let SpecBody::Impl(_, block) = &callable.body.body else {
        panic!("callable body have a block")
    };
    expect![[r#"
        Block 4 [39-56] [Type Int]:
            Stmt 5 [49-50]: Expr: Expr 8 [49-50] [Type Int]: Lit: Int(2)"#]]
    .assert_eq(&block.to_string());
}

#[test]
fn insert_core_call() {
    struct Inserter<'a> {
        core: &'a global::Table,
    }

    impl MutVisitor for Inserter<'_> {
        fn visit_block(&mut self, block: &mut Block) {
            let ns = self
                .core
                .find_namespace(["QIR", "Runtime"].iter().copied())
                .expect("QIR runtime should be inserted at instantiation of core Table");
            let allocate = self
                .core
                .resolve_term(ns, "__quantum__rt__qubit_allocate")
                .expect("qubit allocation should be in core");
            let allocate_ty = allocate
                .scheme
                .instantiate(&[])
                .expect("qubit allocation scheme should instantiate");
            let callee = Expr {
                id: NodeId::default(),
                span: Span::default(),
                ty: Ty::Arrow(Rc::new(allocate_ty)),
                kind: ExprKind::Var(Res::Item(allocate.id), Vec::new()),
            };

            let arg = Expr {
                id: NodeId::default(),
                span: Span::default(),
                ty: Ty::UNIT,
                kind: ExprKind::Tuple(Vec::new()),
            };

            let call = Expr {
                id: NodeId::default(),
                span: Span::default(),
                ty: Ty::Prim(Prim::Qubit),
                kind: ExprKind::Call(Box::new(callee), Box::new(arg)),
            };

            block.stmts.push(Stmt {
                id: NodeId::default(),
                span: Span::default(),
                kind: StmtKind::Semi(call),
            });
        }
    }

    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace A {
                    operation Foo() : () {}
                }
            "}
            .into(),
        )],
        None,
    );

    let store = PackageStore::new(super::core());
    let mut unit = default_compile(sources);
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);
    let mut inserter = Inserter { core: store.core() };
    inserter.visit_package(&mut unit.package);
    unit.assigner.visit_package(&mut unit.package);

    expect![[r#"
        Package:
            Item 0 [0-43] (Public):
                Namespace (Ident 5 [10-11] "A"): Item 1
            Item 1 [18-41] (Internal):
                Parent: 0
                Callable 0 [18-41] (operation):
                    name: Ident 1 [28-31] "Foo"
                    input: Pat 2 [31-33] [Type Unit]: Unit
                    output: Unit
                    functors: empty set
                    body: SpecDecl 3 [18-41]: Impl:
                        Block 4 [39-41] [Type Unit]:
                            Stmt 6 [0-0]: Semi: Expr 7 [0-0] [Type Qubit]: Call:
                                Expr 8 [0-0] [Type (Unit => Qubit)]: Var: Item 4 (Package 0)
                                Expr 9 [0-0] [Type Unit]: Unit
                    adj: <none>
                    ctl: <none>
                    ctl-adj: <none>"#]]
    .assert_eq(&unit.package.to_string());
}

#[test]
fn package_dependency() {
    let mut store = PackageStore::new(super::core());

    let sources1 = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Package1 {
                    function Foo() : Int {
                        1
                    }
                    export Foo;
                }
            "}
            .into(),
        )],
        None,
    );
    let unit1 = compile(
        &store,
        &[],
        sources1,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(unit1.errors.is_empty(), "{:#?}", unit1.errors);
    let package1 = store.insert(unit1);

    let sources2 = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Package2 {
                    function Bar() : Int {
                        PackageAlias.Package1.Foo()
                    }
                }
            "}
            .into(),
        )],
        None,
    );
    let unit2 = compile(
        &store,
        &[(package1, Some(Arc::from("PackageAlias")))],
        sources2,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(unit2.errors.is_empty(), "{:#?}", unit2.errors);

    expect![[r#"
        Package:
            Item 0 [0-91] (Public):
                Namespace (Ident 9 [10-18] "Package2"): Item 1
            Item 1 [25-89] (Internal):
                Parent: 0
                Callable 0 [25-89] (function):
                    name: Ident 1 [34-37] "Bar"
                    input: Pat 2 [37-39] [Type Unit]: Unit
                    output: Int
                    functors: empty set
                    body: SpecDecl 3 [25-89]: Impl:
                        Block 4 [46-89] [Type Int]:
                            Stmt 5 [56-83]: Expr: Expr 6 [56-83] [Type Int]: Call:
                                Expr 7 [56-81] [Type (Unit -> Int)]: Var: Item 1 (Package 1)
                                Expr 8 [81-83] [Type Unit]: Unit
                    adj: <none>
                    ctl: <none>
                    ctl-adj: <none>"#]]
    .assert_eq(&unit2.package.to_string());
}

#[test]
fn package_dependency_internal_error() {
    let mut store = PackageStore::new(super::core());

    let sources1 = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Package1 {
                    internal function Foo() : Int {
                        1
                    }
                }
            "}
            .into(),
        )],
        None,
    );
    let unit1 = compile(
        &store,
        &[],
        sources1,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(unit1.errors.is_empty(), "{:#?}", unit1.errors);
    let package1 = store.insert(unit1);

    let sources2 = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Package2 {
                    function Bar() : Int {
                        Package1.Foo()
                    }
                }
            "}
            .into(),
        )],
        None,
    );
    let unit2 = compile(
        &store,
        &[(package1, Some(Arc::from("PackageAlias")))],
        sources2,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );

    let errors: Vec<_> = unit2
        .errors
        .iter()
        .map(|error| source_span(&unit2.sources, error))
        .collect();
    assert_eq!(vec![("test", Span { lo: 56, hi: 68 }),], errors);

    expect![[r#"
        Package:
            Item 0 [0-78] (Public):
                Namespace (Ident 9 [10-18] "Package2"): Item 1
            Item 1 [25-76] (Internal):
                Parent: 0
                Callable 0 [25-76] (function):
                    name: Ident 1 [34-37] "Bar"
                    input: Pat 2 [37-39] [Type Unit]: Unit
                    output: Int
                    functors: empty set
                    body: SpecDecl 3 [25-76]: Impl:
                        Block 4 [46-76] [Type Int]:
                            Stmt 5 [56-70]: Expr: Expr 6 [56-70] [Type Int]: Call:
                                Expr 7 [56-68] [Type ?]: Var: Err
                                Expr 8 [68-70] [Type Unit]: Unit
                    adj: <none>
                    ctl: <none>
                    ctl-adj: <none>"#]]
    .assert_eq(&unit2.package.to_string());
}

#[test]
fn package_dependency_udt() {
    let mut store = PackageStore::new(super::core());

    let sources1 = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Package1 {
                    newtype Bar = Int;
                    function Foo(bar : Bar) : Int {
                        bar!
                    }
                    export Foo, Bar;
                }
            "}
            .into(),
        )],
        None,
    );
    let unit1 = compile(
        &store,
        &[],
        sources1,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(unit1.errors.is_empty(), "{:#?}", unit1.errors);
    let package1 = store.insert(unit1);

    let sources2 = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Package2 {
                    function Baz() : Int {
                        PackageAlias.Package1.Foo(PackageAlias.Package1.Bar(1))
                    }
                }
            "}
            .into(),
        )],
        None,
    );
    let unit2 = compile(
        &store,
        &[(package1, Some(Arc::from("PackageAlias")))],
        sources2,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(unit2.errors.is_empty(), "{:#?}", unit2.errors);

    expect![[r#"
        Package:
            Item 0 [0-119] (Public):
                Namespace (Ident 11 [10-18] "Package2"): Item 1
            Item 1 [25-117] (Internal):
                Parent: 0
                Callable 0 [25-117] (function):
                    name: Ident 1 [34-37] "Baz"
                    input: Pat 2 [37-39] [Type Unit]: Unit
                    output: Int
                    functors: empty set
                    body: SpecDecl 3 [25-117]: Impl:
                        Block 4 [46-117] [Type Int]:
                            Stmt 5 [56-111]: Expr: Expr 6 [56-111] [Type Int]: Call:
                                Expr 7 [56-81] [Type (UDT<"Bar": Item 1 (Package 1)> -> Int)]: Var: Item 2 (Package 1)
                                Expr 8 [82-110] [Type UDT<"Bar": Item 1 (Package 1)>]: Call:
                                    Expr 9 [82-107] [Type (Int -> UDT<"Bar": Item 1 (Package 1)>)]: Var: Item 1 (Package 1)
                                    Expr 10 [108-109] [Type Int]: Lit: Int(1)
                    adj: <none>
                    ctl: <none>
                    ctl-adj: <none>"#]]
    .assert_eq(&unit2.package.to_string());
}

#[test]
fn package_dependency_nested_udt() {
    let mut store = PackageStore::new(super::core());

    let sources1 = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Package1 {
                    newtype Bar = Int;
                    newtype Baz = Int;
                    newtype Foo = (bar : Bar, Baz);
                    export Bar, Baz, Foo;
                }
            "}
            .into(),
        )],
        None,
    );
    let unit1 = compile(
        &store,
        &[],
        sources1,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(unit1.errors.is_empty(), "{:#?}", unit1.errors);
    let package1 = store.insert(unit1);

    let sources2 = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Package2 {
                    import PackageAlias.*;
                    function Test() : Int {
                        let bar = Package1.Bar(1);
                        let baz = Package1.Baz(2);
                        let foo = Package1.Foo(bar, baz);
                        let inner : Package1.Bar = foo::bar;
                        let (_, other : Package1.Baz) = foo!;
                        inner!
                    }
                }
            "}
            .into(),
        )],
        None,
    );
    let unit2 = compile(
        &store,
        &[(package1, Some(Arc::from("PackageAlias")))],
        sources2,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(unit2.errors.is_empty(), "{:#?}", unit2.errors);

    expect![[r#"
        Package:
            Item 0 [0-301] (Public):
                Namespace (Ident 40 [10-18] "Package2"): Item 1
            Item 1 [52-299] (Internal):
                Parent: 0
                Callable 0 [52-299] (function):
                    name: Ident 1 [61-65] "Test"
                    input: Pat 2 [65-67] [Type Unit]: Unit
                    output: Int
                    functors: empty set
                    body: SpecDecl 3 [52-299]: Impl:
                        Block 4 [74-299] [Type Int]:
                            Stmt 5 [84-110]: Local (Immutable):
                                Pat 6 [88-91] [Type UDT<"Bar": Item 1 (Package 1)>]: Bind: Ident 7 [88-91] "bar"
                                Expr 8 [94-109] [Type UDT<"Bar": Item 1 (Package 1)>]: Call:
                                    Expr 9 [94-106] [Type (Int -> UDT<"Bar": Item 1 (Package 1)>)]: Var: Item 1 (Package 1)
                                    Expr 10 [107-108] [Type Int]: Lit: Int(1)
                            Stmt 11 [119-145]: Local (Immutable):
                                Pat 12 [123-126] [Type UDT<"Baz": Item 2 (Package 1)>]: Bind: Ident 13 [123-126] "baz"
                                Expr 14 [129-144] [Type UDT<"Baz": Item 2 (Package 1)>]: Call:
                                    Expr 15 [129-141] [Type (Int -> UDT<"Baz": Item 2 (Package 1)>)]: Var: Item 2 (Package 1)
                                    Expr 16 [142-143] [Type Int]: Lit: Int(2)
                            Stmt 17 [154-187]: Local (Immutable):
                                Pat 18 [158-161] [Type UDT<"Foo": Item 3 (Package 1)>]: Bind: Ident 19 [158-161] "foo"
                                Expr 20 [164-186] [Type UDT<"Foo": Item 3 (Package 1)>]: Call:
                                    Expr 21 [164-176] [Type ((UDT<"Bar": Item 1 (Package 1)>, UDT<"Baz": Item 2 (Package 1)>) -> UDT<"Foo": Item 3 (Package 1)>)]: Var: Item 3 (Package 1)
                                    Expr 22 [176-186] [Type (UDT<"Bar": Item 1 (Package 1)>, UDT<"Baz": Item 2 (Package 1)>)]: Tuple:
                                        Expr 23 [177-180] [Type UDT<"Bar": Item 1 (Package 1)>]: Var: Local 7
                                        Expr 24 [182-185] [Type UDT<"Baz": Item 2 (Package 1)>]: Var: Local 13
                            Stmt 25 [196-232]: Local (Immutable):
                                Pat 26 [200-220] [Type UDT<"Bar": Item 1 (Package 1)>]: Bind: Ident 27 [200-205] "inner"
                                Expr 28 [223-231] [Type UDT<"Bar": Item 1 (Package 1)>]: Field:
                                    Expr 29 [223-226] [Type UDT<"Foo": Item 3 (Package 1)>]: Var: Local 19
                                    Path(FieldPath { indices: [0] })
                            Stmt 30 [241-278]: Local (Immutable):
                                Pat 31 [245-270] [Type (UDT<"Bar": Item 1 (Package 1)>, UDT<"Baz": Item 2 (Package 1)>)]: Tuple:
                                    Pat 32 [246-247] [Type UDT<"Bar": Item 1 (Package 1)>]: Discard
                                    Pat 33 [249-269] [Type UDT<"Baz": Item 2 (Package 1)>]: Bind: Ident 34 [249-254] "other"
                                Expr 35 [273-277] [Type (UDT<"Bar": Item 1 (Package 1)>, UDT<"Baz": Item 2 (Package 1)>)]: UnOp (Unwrap):
                                    Expr 36 [273-276] [Type UDT<"Foo": Item 3 (Package 1)>]: Var: Local 19
                            Stmt 37 [287-293]: Expr: Expr 38 [287-293] [Type Int]: UnOp (Unwrap):
                                Expr 39 [287-292] [Type UDT<"Bar": Item 1 (Package 1)>]: Var: Local 27
                    adj: <none>
                    ctl: <none>
                    ctl-adj: <none>"#]]
    .assert_eq(&unit2.package.to_string());
}

#[test]
fn std_dependency() {
    let mut store = PackageStore::new(super::core());
    let std = store.insert(super::std(&store, TargetCapabilityFlags::all()));
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    import Std.Intrinsic.*;

                    operation Main() : Unit {
                        use q = Qubit();
                        X(q);
                    }
                }
            "}
            .into(),
        )],
        Some("Foo.Main()".into()),
    );

    let unit = compile(
        &store,
        &[(std, None)],
        sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);
}

#[test]
fn std_dependency_base_profile() {
    let mut store = PackageStore::new(super::core());
    let std = store.insert(super::std(&store, TargetCapabilityFlags::empty()));
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    import Std.Intrinsic.*;

                    operation Main() : Unit {
                        use q = Qubit();
                        X(q);
                    }
                }
            "}
            .into(),
        )],
        Some("Foo.Main()".into()),
    );

    let unit = compile(
        &store,
        &[(std, None)],
        sources,
        TargetCapabilityFlags::empty(),
        LanguageFeatures::default(),
    );
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);
}

#[test]
fn introduce_prelude_ambiguity() {
    let mut store = PackageStore::new(super::core());
    let std = store.insert(super::std(&store, TargetCapabilityFlags::all()));
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"namespace Microsoft.Quantum.Canon {
                function Length () : () { }
            }
                namespace Foo {
                    function Main (): () { Length }
                }"}
            .into(),
        )],
        Some("Foo.Main()".into()),
    );

    let unit = compile(
        &store,
        &[(std, None)],
        sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    let errors: Vec<Error> = unit.errors;
    assert!(
        errors.len() == 1
            && matches!(
                errors[0],
                Error(super::ErrorKind::Resolve(
                    super::resolve::Error::AmbiguousPrelude { .. }
                ))
            )
    );
}

#[test]
fn entry_parse_error() {
    let sources = SourceMap::new(
        [(
            "test".into(),
            "namespace Foo { operation B() : Unit {} }".into(),
        )],
        Some("Foo.B)".into()),
    );

    let unit = default_compile(sources);

    assert_eq!(
        unit.errors[0]
            .code()
            .expect("expected error code")
            .to_string(),
        "Qsc.Parse.Token"
    );

    assert_eq!(
        ("<entry>", Span { lo: 5, hi: 6 }),
        source_span(&unit.sources, &unit.errors[0])
    );
}

#[test]
fn two_files_error_eof() {
    let sources = SourceMap::new(
        [
            ("test1".into(), "namespace Foo {".into()),
            ("test2".into(), "namespace Bar {}".into()),
        ],
        None,
    );

    let unit = default_compile(sources);
    let errors: Vec<_> = unit
        .errors
        .iter()
        .map(|error| source_span(&unit.sources, error))
        .collect();

    assert_eq!(vec![("test1", Span { lo: 15, hi: 15 }),], errors);

    expect![[r#"
        Package:
            Item 0 [0-15] (Public):
                Namespace (Ident 0 [10-13] "Foo"): <empty>
            Item 1 [16-32] (Public):
                Namespace (Ident 1 [26-29] "Bar"): <empty>"#]]
    .assert_eq(&unit.package.to_string());
}

// this test is ignored for now -- see
// https://github.com/microsoft/qsharp/pull/1698#discussion_r1664575343 for more information.
// if we want to use `Unimplemented` more seriously (it is currently not used anywhere),
// we should consider how it will interact with exports and other features.
#[ignore]
#[test]
fn unimplemented_call_from_dependency_produces_error() {
    let lib_sources = SourceMap::new(
        [(
            "lib".into(),
            indoc! {"
                namespace Foo {
                    @Unimplemented()
                    operation Bar() : Unit {}
                }
            "}
            .into(),
        )],
        None,
    );
    let mut store = PackageStore::new(super::core());
    let lib = compile(
        &store,
        &[],
        lib_sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(lib.errors.is_empty(), "{:#?}", lib.errors);
    let lib = store.insert(lib);

    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Test {
                    open Foo;
                    operation Main() : Unit {
                        Bar();
                    }
                }
            "}
            .into(),
        )],
        None,
    );
    let unit = compile(
        &store,
        &[(lib, None)],
        sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    expect![[r#"
        [
           Error(
               Resolve(
                   Unimplemented(
                        "Bar",
                        Span {
                           lo: 69,
                           hi: 72,
                        },
                   ),
               ),
           ),
        ]
    "#]]
    .assert_debug_eq(&unit.errors);
}

#[test]
fn unimplemented_attribute_call_within_unit_error() {
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    @Unimplemented()
                    operation Bar() : Unit {}
                    operation Baz() : Unit {
                        Bar();
                    }
                }
            "}
            .into(),
        )],
        None,
    );
    let unit = default_compile(sources);
    expect![[r#"
        [
            Error(
                Resolve(
                    Unimplemented(
                        "Bar",
                        Span {
                            lo: 104,
                            hi: 107,
                        },
                    ),
                ),
            ),
        ]
    "#]]
    .assert_debug_eq(&unit.errors);
}

#[test]
fn unimplemented_attribute_with_non_unit_expr_error() {
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    @Unimplemented(1)
                    operation Bar() : Unit {}
                }
            "}
            .into(),
        )],
        None,
    );
    let unit = default_compile(sources);
    expect![[r#"
        [
            Error(
                Lower(
                    InvalidAttrArgs(
                        "()",
                        Span {
                            lo: 34,
                            hi: 37,
                        },
                    ),
                ),
            ),
        ]
    "#]]
    .assert_debug_eq(&unit.errors);
}

#[test]
fn unimplemented_attribute_avoids_ambiguous_error_with_duplicate_names_in_scope() {
    let lib_sources = SourceMap::new(
        [(
            "lib".into(),
            indoc! {"
                namespace Foo {
                    @Unimplemented()
                    operation Bar() : Unit {}
                }
            "}
            .into(),
        )],
        None,
    );
    let mut store = PackageStore::new(super::core());
    let lib = compile(
        &store,
        &[],
        lib_sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(lib.errors.is_empty(), "{:#?}", lib.errors);
    let lib = store.insert(lib);

    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Dependency {
                    operation Bar() : Unit {}
                }
                namespace Test {
                    open Foo;
                    open Dependency;
                    operation Main() : Unit {
                        Bar();
                    }
                }
            "}
            .into(),
        )],
        None,
    );
    let unit = compile(
        &store,
        &[(lib, None)],
        sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    expect![[r#"
        []
    "#]]
    .assert_debug_eq(&unit.errors);
}

#[test]
fn duplicate_intrinsic_from_dependency() {
    let lib_sources = SourceMap::new(
        [(
            "lib".into(),
            indoc! {"
                namespace Foo {
                    operation Bar() : Unit { body intrinsic; }
                }
            "}
            .into(),
        )],
        None,
    );

    let mut store = PackageStore::new(super::core());
    let lib = compile(
        &store,
        &[],
        lib_sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(lib.errors.is_empty(), "{:#?}", lib.errors);
    let lib = store.insert(lib);

    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Test {
                    operation Bar() : Unit { body intrinsic; }
                }
            "}
            .into(),
        )],
        None,
    );

    let unit = compile(
        &store,
        &[(lib, None)],
        sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    expect![[r#"
        [
            Error(
                Resolve(
                    DuplicateIntrinsic(
                        "Bar",
                        Span {
                            lo: 31,
                            hi: 34,
                        },
                    ),
                ),
            ),
        ]
    "#]]
    .assert_debug_eq(&unit.errors);
}

#[test]
fn reject_use_qubit_block_syntax_if_preview_feature_is_on() {
    let mut store = PackageStore::new(super::core());
    let std = store.insert(super::std(&store, TargetCapabilityFlags::empty()));
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    import Std.Intrinsic.*;
                    operation Main() : Unit {
                        use q = Qubit() {
                            // some qubit operation here
                            // this should be a syntax error because
                            // we have the v2 preview syntax feature enabled
                            X(q);
                        };

                    }
                }
            "}
            .into(),
        )],
        Some("Foo.Main()".into()),
    );

    let unit = compile(
        &store,
        &[(std, None)],
        sources,
        TargetCapabilityFlags::empty(),
        LanguageFeatures::V2PreviewSyntax,
    );
    expect![[r#"
        [
            Error(
                Parse(
                    Error(
                        Token(
                            Semi,
                            Open(
                                Brace,
                            ),
                            Span {
                                lo: 109,
                                hi: 110,
                            },
                        ),
                    ),
                ),
            ),
        ]
    "#]]
    .assert_debug_eq(&unit.errors);
}

#[test]
fn accept_use_qubit_block_syntax_if_preview_feature_is_off() {
    let mut store = PackageStore::new(super::core());
    let std = store.insert(super::std(&store, TargetCapabilityFlags::empty()));
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace Foo {
                    import Std.Intrinsic.*;
                    operation Main() : Unit {
                        use q = Qubit() {
                            // some qubit operation here
                            // this should be a syntax error because
                            // we have the v2 preview syntax feature enabled
                            X(q);
                        };
                    }
                }
            "}
            .into(),
        )],
        Some("Foo.Main()".into()),
    );

    let unit = compile(
        &store,
        &[(std, None)],
        sources,
        TargetCapabilityFlags::empty(),
        LanguageFeatures::default(),
    );
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);
}

#[test]
fn hierarchical_namespace_basic() {
    let lib_sources = SourceMap::new(
        [(
            "lib".into(),
            indoc! {"
                namespace Foo.Bar {
                    operation Baz() : Unit {}
                }
                namespace Main {
                    open Foo;
                    operation Main() : Unit {
                        Bar.Baz();
                    }
                }
            "}
            .into(),
        )],
        None,
    );

    let store = PackageStore::new(super::core());
    let lib = compile(
        &store,
        &[],
        lib_sources,
        TargetCapabilityFlags::all(),
        LanguageFeatures::default(),
    );
    assert!(lib.errors.is_empty(), "{:#?}", lib.errors);
}

#[test]
fn implicit_namespace_basic() {
    let sources = SourceMap::new(
        [
            (
                "Test.qs".into(),
                indoc! {"
                    operation Bar() : Unit {}
            "}
                .into(),
            ),
            (
                "Main.qs".into(),
                indoc! {"
                    @EntryPoint()
                    operation Bar() : Unit {
                        Test.Bar();
                        open Foo.Bar;
                        Baz.Quux();
                    }
            "}
                .into(),
            ),
            (
                "Foo/Bar/Baz.qs".into(),
                indoc! {"
                    operation Quux() : Unit {}
            "}
                .into(),
            ),
        ],
        None,
    );
    let unit = default_compile(sources);
    assert!(unit.errors.is_empty(), "{:#?}", unit.errors);
}

#[test]
fn bad_filename_implicit_namespace_best_effort_fixup() {
    let sources = SourceMap::new(
        [
            // Rejected for starting with number
            (
                "123Test.qs".into(),
                indoc! {"
                    operation Bar() : Unit {}
            "}
                .into(),
            ),
            // Cleaned up by replacing '-' with '_'
            (
                "Test-File.qs".into(),
                indoc! {"
                    operation Bar() : Unit {
                    }
            "}
                .into(),
            ),
            // Rejected for containing '.'
            (
                "Namespace.Foo.qs".into(),
                indoc! {"
                    operation Bar() : Unit {}
            "}
                .into(),
            ),
        ],
        None,
    );
    let unit = default_compile(sources);
    expect![[r#"
        [
            Error(
                Parse(
                    Error(
                        InvalidFileName(
                            Span {
                                lo: 0,
                                hi: 25,
                            },
                            "123Test",
                        ),
                    ),
                ),
            ),
            Error(
                Parse(
                    Error(
                        InvalidFileName(
                            Span {
                                lo: 55,
                                hi: 80,
                            },
                            "Namespace.Foo",
                        ),
                    ),
                ),
            ),
        ]
    "#]]
    .assert_debug_eq(&unit.errors);
}

#[test]
fn test_longest_common_prefix_1() {
    assert_eq!(longest_common_prefix(&["/a/b/c", "/a/b/d"]), "/a/b/");
}

#[test]
fn test_longest_common_prefix_2() {
    assert_eq!(longest_common_prefix(&["foo", "bar"]), "");
}

#[test]
fn test_longest_common_prefix_3() {
    assert_eq!(longest_common_prefix(&["baz", "bar"]), "");
}

#[test]
fn test_longest_common_prefix_4() {
    assert_eq!(longest_common_prefix(&["baz", "bar"]), "");
}

#[test]
fn test_longest_common_prefix_5() {
    assert_eq!(
        longest_common_prefix(&[
            "code\\project\\src\\Main.qs",
            "code\\project\\src\\Helper.qs"
        ]),
        "code\\project\\src\\"
    );
}

#[test]
fn test_longest_common_prefix_6() {
    assert_eq!(
        longest_common_prefix(&["code/project/src/Bar.qs", "code/project/src/Baz.qs"]),
        "code/project/src/"
    );
}

#[test]
fn test_longest_common_prefix_two_relative_paths() {
    expect!["a/"].assert_eq(longest_common_prefix(&["a/b", "a/c"]));
}

#[test]
fn test_longest_common_prefix_one_relative_path() {
    expect!["a/"].assert_eq(longest_common_prefix(&["a/b"]));
}

#[test]
fn test_longest_common_prefix_one_file_name() {
    expect![""].assert_eq(longest_common_prefix(&["a"]));
}

#[test]
fn test_longest_common_prefix_only_root_common() {
    expect!["/"].assert_eq(longest_common_prefix(&["/a/b", "/b/c"]));
}

#[test]
fn test_longest_common_prefix_only_root_common_no_leading() {
    expect![""].assert_eq(longest_common_prefix(&["a/b", "b/c"]));
}

#[test]
fn export_namespace_with_same_name_as_newtype_does_not_cause_panic() {
    let sources = SourceMap::new(
        [(
            "test".into(),
            indoc! {"
                namespace A {
                    export A;
                    newtype A = Int;
                }
            "}
            .into(),
        )],
        None,
    );

    let unit = default_compile(sources);
    expect!["[]"].assert_eq(&format!("{:?}", unit.errors));
}
