Support descriptions of executable documents (#1349, #1347, graphql/graphql-spec#1170)

- add `description` field to `ast::Operation`, `ast::Fragment` and `ast::VariableDefinition` (graphql/graphql-spec#1170)
- support full Unicode range (graphql/graphql-spec#849, graphql/graphql-spec#687)
- support parsing block string literals
- support variable-length escaped Unicode characters in strings (graphql/graphql-spec#849, graphql/graphql-spec#687)
- fix incorrect double escaping in `ScalarToken::String` `Display`ing
- change `ScalarToken::String` to contain raw quoted and escaped `StringLiteral`
- add `LexerError::UnterminatedBlockString` variant

Additionally:
- move `String` parsing to `StringLiteral::parse()` method
- move lexer tests to `parser::lexer` module
- satisfy rustc linter when running `juniper` unit tests without features

Author: tyranron

juniper/CHANGELOG.md

@@ -15,19 +15,26 @@ All user visible changes to `juniper` crate will be documented in this file. Thi
 - [September 2025] GraphQL spec: ([#1347])
     - Made `includeDeprecated` argument of `__Type.fields`, `__Type.enumValues`, `__Type.inputFields`, `__Field.args` and `__Directive.args` fields non-`Null`. ([#1348], [graphql/graphql-spec#1142])
     - Made `@deprecated(reason:)` argument non-`Null`. ([#1348], [graphql/graphql-spec#1040])
+    - Added `description` field to `ast::Operation`, `ast::Fragment` and `ast::VariableDefinition`. ([#1349], [graphql/graphql-spec#1170])
+- Changed `ScalarToken::String` to contain raw quoted and escaped `StringLiteral` (was unquoted but escaped string before). ([#1349])
+- Added `LexerError::UnterminatedBlockString` variant. ([#1349])
 
 ### Added
 
 - [September 2025] GraphQL spec: ([#1347])
     - `__Type.isOneOf` field. ([#1348], [graphql/graphql-spec#825])
     - `SCHEMA`, `OBJECT`, `ARGUMENT_DEFINITION`, `INTERFACE`, `UNION`, `ENUM`, `INPUT_OBJECT` and `INPUT_FIELD_DEFINITION` values to `__DirectiveLocation` enum. ([#1348])
-    - Arguments and input object fields deprecation: ([#1348], [#864], [graphql/graphql-spec#525], [graphql/graphql-spec#805]) 
+    - Arguments and input object fields deprecation: ([#1348], [#864], [graphql/graphql-spec#525], [graphql/graphql-spec#805])
         - Placing `#[graphql(deprecated)]` and `#[deprecated]` attributes on struct fields in `#[derive(GraphQLInputObject)]` macro.
         - Placing `#[graphql(deprecated)]` attribute on method arguments in `#[graphql_object]` and `#[graphql_interface]` macros.
         - Placing `@deprecated` directive on arguments and input object fields.
         - `includeDeprecated` argument to `__Type.inputFields`, `__Field.args` and `__Directive.args` fields.
         - `__InputValue.isDeprecated` and `__InputValue.deprecationReason` fields.
         - `schema::meta::Argument::deprecation_status` field.
+    - Support for variable-length escaped Unicode characters (e.g. `\u{110000}`) in strings. ([#1349], [graphql/graphql-spec#849], [graphql/graphql-spec#687])
+    - Full Unicode range support. ([#1349], [graphql/graphql-spec#849], [graphql/graphql-spec#687])
+    - Support parsing descriptions on operations, fragments and variable definitions. ([#1349], [graphql/graphql-spec#1170])
+- Support for [block strings][0180-1]. ([#1349])
 
 ### Changed
 
@@ -38,15 +45,21 @@ All user visible changes to `juniper` crate will be documented in this file. Thi
 
 - Incorrect `__Type.specifiedByUrl` field to `__Type.specifiedByURL`. ([#1348])
 - Missing `@specifiedBy(url:)` directive in [SDL] generated by `RootNode::as_sdl()` and `RootNode::as_document()` methods. ([#1348])
+- Incorrect double escaping in `ScalarToken::String` `Display`ing. ([#1349])
 
 [#864]: /../../issues/864
 [#1347]: /../../issues/1347
 [#1348]: /../../pull/1348
+[#1349]: /../../pull/1349
 [graphql/graphql-spec#525]: https://github.com/graphql/graphql-spec/pull/525
+[graphql/graphql-spec#687]: https://github.com/graphql/graphql-spec/issues/687
 [graphql/graphql-spec#805]: https://github.com/graphql/graphql-spec/pull/805
 [graphql/graphql-spec#825]: https://github.com/graphql/graphql-spec/pull/825
+[graphql/graphql-spec#849]: https://github.com/graphql/graphql-spec/pull/849
 [graphql/graphql-spec#1040]: https://github.com/graphql/graphql-spec/pull/1040
 [graphql/graphql-spec#1142]: https://github.com/graphql/graphql-spec/pull/1142
+[graphql/graphql-spec#1170]: https://github.com/graphql/graphql-spec/pull/1170
+[0180-1]: https://spec.graphql.org/September2025/#sec-String-Value.Block-Strings
 
 
 

juniper/src/ast.rs

@@ -307,6 +307,7 @@ pub enum InputValue<S = DefaultScalarValue> {
 
 #[derive(Clone, Debug, PartialEq)]
 pub struct VariableDefinition<'a, S> {
+    pub description: Option<Spanning<Cow<'a, str>>>,
     pub var_type: Spanning<Type<&'a str>>,
     pub default_value: Option<Spanning<InputValue<S>>>,
     pub directives: Option<Vec<Spanning<Directive<'a, S>>>>,
@@ -384,6 +385,7 @@ pub enum OperationType {
 #[expect(missing_docs, reason = "self-explanatory")]
 #[derive(Clone, Debug, PartialEq)]
 pub struct Operation<'a, S> {
+    pub description: Option<Spanning<Cow<'a, str>>>,
     pub operation_type: OperationType,
     pub name: Option<Spanning<&'a str>>,
     pub variable_definitions: Option<Spanning<VariableDefinitions<'a, S>>>,
@@ -394,6 +396,7 @@ pub struct Operation<'a, S> {
 #[derive(Clone, Debug, PartialEq)]
 pub struct Fragment<'a, S> {
     pub name: Spanning<&'a str>,
+    pub description: Option<Spanning<Cow<'a, str>>>,
     pub type_condition: Spanning<&'a str>,
     pub directives: Option<Vec<Spanning<Directive<'a, S>>>>,
     pub selection_set: Vec<Selection<'a, S>>,
@@ -406,6 +409,16 @@ pub enum Definition<'a, S> {
     Fragment(Spanning<Fragment<'a, S>>),
 }
 
+impl<'a, S> Definition<'a, S> {
+    /// Sets or resets the provided `description` for this [`Definition`].
+    pub(crate) fn set_description(&mut self, description: Option<Spanning<Cow<'a, str>>>) {
+        match self {
+            Self::Operation(op) => op.item.description = description,
+            Self::Fragment(frag) => frag.item.description = description,
+        }
+    }
+}
+
 #[doc(hidden)]
 pub type Document<'a, S> = [Definition<'a, S>];
 #[doc(hidden)]

juniper/src/lib.rs

@@ -13,6 +13,15 @@ extern crate self as juniper;
 mod for_benches_only {
     use bencher as _;
 }
+#[cfg(test)]
+mod for_feature_gated_tests_only {
+    #[cfg(not(feature = "chrono"))]
+    use chrono as _;
+    #[cfg(not(feature = "jiff"))]
+    use jiff as _;
+    #[cfg(not(feature = "anyhow"))]
+    use serial_test as _;
+}
 
 // These are required by the code generated via the `juniper_codegen` macros.
 #[doc(hidden)]
@@ -87,7 +96,7 @@ pub use crate::{
     },
     introspection::IntrospectionFormat,
     macros::helper::subscription::{ExtractTypeFromStream, IntoFieldResult},
-    parser::{ParseError, ScalarToken, Span, Spanning},
+    parser::{ParseError, ScalarToken, Span, Spanning, StringLiteral},
     schema::{
         meta,
         model::{RootNode, SchemaType},

juniper/src/parser/document.rs

@@ -1,12 +1,13 @@
-use crate::ast::{
-    Arguments, Definition, Directive, Field, Fragment, FragmentSpread, InlineFragment, InputValue,
-    Operation, OperationType, OwnedDocument, Selection, Type, VariableDefinition,
-    VariableDefinitions,
-};
+use std::borrow::Cow;
 
 use crate::{
+    ast::{
+        Arguments, Definition, Directive, Field, Fragment, FragmentSpread, InlineFragment,
+        InputValue, Operation, OperationType, OwnedDocument, Selection, Type, VariableDefinition,
+        VariableDefinitions,
+    },
     parser::{
-        Lexer, OptionParseResult, ParseError, ParseResult, Parser, Spanning, Token,
+        Lexer, OptionParseResult, ParseError, ParseResult, Parser, ScalarToken, Spanning, Token,
         UnlocatedParseResult, value::parse_value_literal,
     },
     schema::{
@@ -25,7 +26,7 @@ where
     S: ScalarValue,
 {
     let mut lexer = Lexer::new(s);
-    let mut parser = Parser::new(&mut lexer).map_err(|s| s.map(ParseError::LexerError))?;
+    let mut parser = Parser::new(&mut lexer).map_err(|s| s.map(Into::into))?;
     parse_document(&mut parser, schema)
 }
 
@@ -54,18 +55,25 @@ fn parse_definition<'a, S>(
 where
     S: ScalarValue,
 {
-    match parser.peek().item {
+    let description = parse_description(parser)?;
+
+    let mut def = match parser.peek().item {
+        // Descriptions are not permitted on query shorthand.
+        // See: https://spec.graphql.org/September2025#sel-GAFTRJABAByBz7P
+        Token::CurlyOpen if description.is_some() => {
+            return Err(parser.next_token()?.map(ParseError::unexpected_token));
+        }
         Token::CurlyOpen
         | Token::Name("query")
         | Token::Name("mutation")
-        | Token::Name("subscription") => Ok(Definition::Operation(parse_operation_definition(
-            parser, schema,
-        )?)),
-        Token::Name("fragment") => Ok(Definition::Fragment(parse_fragment_definition(
-            parser, schema,
-        )?)),
-        _ => Err(parser.next_token()?.map(ParseError::unexpected_token)),
-    }
+        | Token::Name("subscription") => {
+            Definition::Operation(parse_operation_definition(parser, schema)?)
+        }
+        Token::Name("fragment") => Definition::Fragment(parse_fragment_definition(parser, schema)?),
+        _ => return Err(parser.next_token()?.map(ParseError::unexpected_token)),
+    };
+    def.set_description(description);
+    Ok(def)
 }
 
 fn parse_operation_definition<'a, S>(
@@ -85,6 +93,7 @@ where
             Operation {
                 operation_type: OperationType::Query,
                 name: None,
+                description: None,
                 variable_definitions: None,
                 directives: None,
                 selection_set: selection_set.item,
@@ -115,6 +124,7 @@ where
             Operation {
                 operation_type: operation_type.item,
                 name,
+                description: None,
                 variable_definitions,
                 directives: directives.map(|s| s.item),
                 selection_set: selection_set.item,
@@ -158,6 +168,7 @@ where
         &selection_set.span.end,
         Fragment {
             name,
+            description: None,
             type_condition: type_cond,
             directives: directives.map(|s| s.item),
             selection_set: selection_set.item,
@@ -429,6 +440,8 @@ fn parse_variable_definition<'a, S>(
 where
     S: ScalarValue,
 {
+    let description = parse_description(parser)?;
+
     let start_pos = parser.expect(&Token::Dollar)?.span.start;
     let var_name = parser.expect_name()?;
     parser.expect(&Token::Colon)?;
@@ -452,6 +465,7 @@ where
         (
             Spanning::start_end(&start_pos, &var_name.span.end, var_name.item),
             VariableDefinition {
+                description,
                 var_type,
                 default_value,
                 directives: directives.map(|s| s.item),
@@ -460,6 +474,21 @@ where
     ))
 }
 
+fn parse_description<'a>(parser: &mut Parser<'a>) -> OptionParseResult<Cow<'a, str>> {
+    if !matches!(parser.peek().item, Token::Scalar(ScalarToken::String(_))) {
+        Ok(None)
+    } else {
+        let token = parser.next_token()?;
+        let Token::Scalar(ScalarToken::String(lit)) = token.item else {
+            unreachable!("already checked to be `ScalarToken::String`")
+        };
+        Ok(Some(Spanning::new(
+            token.span,
+            lit.parse().map_err(|e| Spanning::new(token.span, e))?,
+        )))
+    }
+}
+
 fn parse_directives<'a, S>(
     parser: &mut Parser<'a>,
     schema: &SchemaType<S>,