feat: add fmtstr::quoted_contents

compiler/noirc_frontend/src/hir/comptime/interpreter.rs

@@ -586,7 +586,19 @@ impl<'local, 'interner> Interpreter<'local, 'interner> {
                     consuming = false;
 
                     if let Some(value) = values.pop_front() {
-                        result.push_str(&value.display(self.elaborator.interner).to_string());
+                        // When interpolating a quoted value inside a format string, we don't include the
+                        // surrounding `quote {` ... `}` as if we are unquoting the quoted value inside the string.
+                        if let Value::Quoted(tokens) = value {
+                            for (index, token) in tokens.iter().enumerate() {
+                                if index > 0 {
+                                    result.push(' ');
+                                }
+                                result
+                                    .push_str(&token.display(self.elaborator.interner).to_string());
+                            }
+                        } else {
+                            result.push_str(&value.display(self.elaborator.interner).to_string());
+                        }
                     }
                 }
                 other if !consuming => {

compiler/noirc_frontend/src/hir/comptime/interpreter/builtin.rs

@@ -7,9 +7,9 @@ use acvm::{AcirField, FieldElement};
 use builtin_helpers::{
     block_expression_to_value, check_argument_count, check_function_not_yet_resolved,
     check_one_argument, check_three_arguments, check_two_arguments, get_expr, get_field,
-    get_function_def, get_module, get_quoted, get_slice, get_struct, get_trait_constraint,
-    get_trait_def, get_trait_impl, get_tuple, get_type, get_typed_expr, get_u32,
-    get_unresolved_type, hir_pattern_to_tokens, mutate_func_meta_type, parse,
+    get_format_string, get_function_def, get_module, get_quoted, get_slice, get_struct,
+    get_trait_constraint, get_trait_def, get_trait_impl, get_tuple, get_type, get_typed_expr,
+    get_u32, get_unresolved_type, hir_pattern_to_tokens, mutate_func_meta_type, parse,
     replace_func_meta_parameters, replace_func_meta_return_type,
 };
 use chumsky::{prelude::choice, Parser};
@@ -32,6 +32,7 @@ use crate::{
         InterpreterError, Value,
     },
     hir_def::function::FunctionBody,
+    lexer::Lexer,
     macros_api::{HirExpression, HirLiteral, ModuleDefId, NodeInterner, Signedness},
     node_interner::{DefinitionKind, TraitImplKind},
     parser::{self},
@@ -95,6 +96,7 @@ impl<'local, 'context> Interpreter<'local, 'context> {
             "expr_is_continue" => expr_is_continue(interner, arguments, location),
             "expr_resolve" => expr_resolve(self, arguments, location),
             "is_unconstrained" => Ok(Value::Bool(true)),
+            "fmtstr_contents" => fmtstr_contents(interner, arguments, location),
             "function_def_body" => function_def_body(interner, arguments, location),
             "function_def_has_named_attribute" => {
                 function_def_has_named_attribute(interner, arguments, location)
@@ -1576,6 +1578,23 @@ fn unwrap_expr_value(interner: &NodeInterner, mut expr_value: ExprValue) -> Expr
     expr_value
 }
 
+// fn contents(self) -> Quoted
+fn fmtstr_contents(
+    interner: &NodeInterner,
+    arguments: Vec<(Value, Location)>,
+    location: Location,
+) -> IResult<Value> {
+    let self_argument = check_one_argument(arguments, location)?;
+    let (string, _) = get_format_string(interner, self_argument)?;
+    let (tokens, _) = Lexer::lex(&string);
+    let mut tokens: Vec<_> = tokens.0.into_iter().map(|token| token.into_token()).collect();
+    if let Some(Token::EOF) = tokens.last() {
+        tokens.pop();
+    }
+
+    Ok(Value::Quoted(Rc::new(tokens)))
+}
+
 // fn body(self) -> Expr
 fn function_def_body(
     interner: &NodeInterner,

compiler/noirc_frontend/src/hir/comptime/interpreter/builtin/builtin_helpers.rs

@@ -189,6 +189,20 @@ pub(crate) fn get_expr(
     }
 }
 
+pub(crate) fn get_format_string(
+    interner: &NodeInterner,
+    (value, location): (Value, Location),
+) -> IResult<(Rc<String>, Type)> {
+    match value {
+        Value::FormatString(value, typ) => Ok((value, typ)),
+        value => {
+            let n = Box::new(interner.next_type_variable());
+            let e = Box::new(interner.next_type_variable());
+            type_mismatch(value, Type::FmtString(n, e), location)
+        }
+    }
+}
+
 pub(crate) fn get_function_def((value, location): (Value, Location)) -> IResult<FuncId> {
     match value {
         Value::FunctionDefinition(id) => Ok(id),

compiler/noirc_frontend/src/hir/comptime/value.rs

@@ -605,33 +605,7 @@ impl<'value, 'interner> Display for ValuePrinter<'value, 'interner> {
                 write!(f, "quote {{")?;
                 for token in tokens.iter() {
                     write!(f, " ")?;
-
-                    match token {
-                        Token::QuotedType(id) => {
-                            write!(f, "{}", self.interner.get_quoted_type(*id))?;
-                        }
-                        Token::InternedExpr(id) => {
-                            let value = Value::expression(ExpressionKind::Interned(*id));
-                            value.display(self.interner).fmt(f)?;
-                        }
-                        Token::InternedStatement(id) => {
-                            let value = Value::statement(StatementKind::Interned(*id));
-                            value.display(self.interner).fmt(f)?;
-                        }
-                        Token::InternedLValue(id) => {
-                            let value = Value::lvalue(LValue::Interned(*id, Span::default()));
-                            value.display(self.interner).fmt(f)?;
-                        }
-                        Token::InternedUnresolvedTypeData(id) => {
-                            let value = Value::UnresolvedType(UnresolvedTypeData::Interned(*id));
-                            value.display(self.interner).fmt(f)?;
-                        }
-                        Token::UnquoteMarker(id) => {
-                            let value = Value::TypedExpr(TypedExpr::ExprId(*id));
-                            value.display(self.interner).fmt(f)?;
-                        }
-                        other => write!(f, "{other}")?,
-                    }
+                    token.display(self.interner).fmt(f)?;
                 }
                 write!(f, " }}")
             }
@@ -713,6 +687,51 @@ impl<'value, 'interner> Display for ValuePrinter<'value, 'interner> {
     }
 }
 
+impl Token {
+    pub fn display<'token, 'interner>(
+        &'token self,
+        interner: &'interner NodeInterner,
+    ) -> TokenPrinter<'token, 'interner> {
+        TokenPrinter { token: self, interner }
+    }
+}
+
+pub struct TokenPrinter<'token, 'interner> {
+    token: &'token Token,
+    interner: &'interner NodeInterner,
+}
+
+impl<'token, 'interner> Display for TokenPrinter<'token, 'interner> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self.token {
+            Token::QuotedType(id) => {
+                write!(f, "{}", self.interner.get_quoted_type(*id))
+            }
+            Token::InternedExpr(id) => {
+                let value = Value::expression(ExpressionKind::Interned(*id));
+                value.display(self.interner).fmt(f)
+            }
+            Token::InternedStatement(id) => {
+                let value = Value::statement(StatementKind::Interned(*id));
+                value.display(self.interner).fmt(f)
+            }
+            Token::InternedLValue(id) => {
+                let value = Value::lvalue(LValue::Interned(*id, Span::default()));
+                value.display(self.interner).fmt(f)
+            }
+            Token::InternedUnresolvedTypeData(id) => {
+                let value = Value::UnresolvedType(UnresolvedTypeData::Interned(*id));
+                value.display(self.interner).fmt(f)
+            }
+            Token::UnquoteMarker(id) => {
+                let value = Value::TypedExpr(TypedExpr::ExprId(*id));
+                value.display(self.interner).fmt(f)
+            }
+            other => write!(f, "{other}"),
+        }
+    }
+}
+
 fn display_trait_constraint(interner: &NodeInterner, trait_constraint: &TraitConstraint) -> String {
     let trait_ = interner.get_trait(trait_constraint.trait_id);
     format!("{}: {}{}", trait_constraint.typ, trait_.name, trait_constraint.trait_generics)

docs/docs/noir/standard_library/meta/fmtstr.md

@@ -0,0 +1,13 @@
+---
+title: fmtstr
+---
+
+`std::meta::format_string` contains comptime methods on the `fmtstr` type for format strings.
+
+## Methods
+
+### contents
+
+#include_code contents noir_stdlib/src/meta/format_string.nr rust
+
+Returns the format string contents (that is, without the leading and trailing double quotes) as a `Quoted` value.

noir_stdlib/src/meta/format_string.nr

@@ -0,0 +1,6 @@
+impl <let N: u32, T> fmtstr<N, T> {
+    #[builtin(fmtstr_contents)]
+    // docs:start:contents
+    fn contents(self) -> Quoted {}
+    // docs:end:contents
+}

noir_stdlib/src/meta/mod.nr

@@ -1,4 +1,5 @@
 mod expr;
+mod format_string;
 mod function_def;
 mod module;
 mod op;

test_programs/compile_success_empty/comptime_fmt_strings/src/main.nr

@@ -12,4 +12,18 @@ fn main() {
     };
     assert_eq(s1, "x is 4, fake interpolation: {y}, y is 5");
     assert_eq(s2, "\0\0\0\0");
+
+    // Mainly test fmtstr::contents
+    call!(glue(quote { hello }, quote { world }));
+}
+
+fn glue(x: Quoted, y: Quoted) -> Quoted {
+    f"{x}_{y}".contents()
 }
+
+fn hello_world() {}
+
+comptime fn call(x: Quoted) -> Quoted {
+    quote { $x() }
+}
+

test_programs/compile_success_empty/unquote_struct/src/main.nr

@@ -10,11 +10,13 @@ fn foo(x: Field, y: u32) -> u32 {
 
 // Given a function, wrap its parameters in a struct definition
 comptime fn output_struct(f: FunctionDefinition) -> Quoted {
-    let fields = f.parameters().map(|param: (Quoted, Type)| {
+    let fields = f.parameters().map(
+        |param: (Quoted, Type)| {
         let name = param.0;
         let typ = param.1;
         quote { $name: $typ, }
-    }).join(quote {});
+    }
+    ).join(quote {});
 
     quote {
         struct Foo { $fields }

tooling/lsp/src/requests/completion/tests.rs

@@ -336,7 +336,7 @@ mod completion_tests {
             fo>|<
           }
         "#;
-        assert_completion(src, vec![module_completion_item("foobar")]).await;
+        assert_completion_excluding_auto_import(src, vec![module_completion_item("foobar")]).await;
     }
 
     #[test]