Added diagnostic for unsupported operations.

litho-diagnostics/src/lib.rs

@@ -542,6 +542,10 @@ diagnostics! {
         "Fragment `{fragment}` is used here ..." @ span,
         "... and it requires variable `${name}` to be type `{expected}` here ..." @ second,
         "... but variable `${name}` is defined here as type `{ty}`." @ first
+    },
+    E0329 => UnsupportedOperation @ span + name {
+        "Operation must be defined in schema before it can be used.",
+        "Schema doesn't have a `{name}` type. You might be interested in using `@litho(url: \"...\")` to automatically import your existing schema. Learn more at https://litho.dev/docs/operations/import-schemas/." @ span
     }
 }
 

litho-tests/snapshots/E0005

@@ -5,3 +5,12 @@
    ·           ─┬  
    ·            ╰── Missing name of this field here.
 ───╯
+
+
+[E0329] Error: Operation must be defined in schema before it can be used.
+   ╭─[graphql:1:1]
+   │
+ 1 │ query Example {
+   · ──┬──  
+   ·   ╰──── Schema doesn't have a `Query` type. You might be interested in using `@litho(url: "...")` to automatically import your existing schema. Learn more at https://litho.dev/docs/operations/import-schemas/.
+───╯

litho-tests/snapshots/E0011

@@ -5,3 +5,12 @@
    ·                 ┬  
    ·                 ╰── Fragment definition here does not have a type condition.
 ───╯
+
+
+[E0329] Error: Operation must be defined in schema before it can be used.
+   ╭─[graphql:5:1]
+   │
+ 5 │ query {
+   · ──┬──  
+   ·   ╰──── Schema doesn't have a `Query` type. You might be interested in using `@litho(url: "...")` to automatically import your existing schema. Learn more at https://litho.dev/docs/operations/import-schemas/.
+───╯

litho-tests/snapshots/E0013

@@ -5,3 +5,12 @@
    ·                    ┬  
    ·                    ╰── Type condition here does not have a named type.
 ───╯
+
+
+[E0329] Error: Operation must be defined in schema before it can be used.
+   ╭─[graphql:5:1]
+   │
+ 5 │ query {
+   · ──┬──  
+   ·   ╰──── Schema doesn't have a `Query` type. You might be interested in using `@litho(url: "...")` to automatically import your existing schema. Learn more at https://litho.dev/docs/operations/import-schemas/.
+───╯

litho-tests/snapshots/E0100

@@ -23,3 +23,12 @@
     ·            ─────┬─────  
     ·                 ╰─────── Type `NonExistent` is referenced to here but never defined.
 ────╯
+
+
+[E0329] Error: Operation must be defined in schema before it can be used.
+   ╭─[graphql:9:1]
+   │
+ 9 │ query {
+   · ──┬──  
+   ·   ╰──── Schema doesn't have a `Query` type. You might be interested in using `@litho(url: "...")` to automatically import your existing schema. Learn more at https://litho.dev/docs/operations/import-schemas/.
+───╯

litho-tests/snapshots/E0316

@@ -5,3 +5,12 @@
    ·         ────────┬────────  
    ·                 ╰────────── Fragment `undefinedFragment` is used here but never defined.
 ───╯
+
+
+[E0329] Error: Operation must be defined in schema before it can be used.
+   ╭─[graphql:1:1]
+   │
+ 1 │ query {
+   · ──┬──  
+   ·   ╰──── Schema doesn't have a `Query` type. You might be interested in using `@litho(url: "...")` to automatically import your existing schema. Learn more at https://litho.dev/docs/operations/import-schemas/.
+───╯

litho-tests/snapshots/E0329

@@ -0,0 +1,25 @@
+[E0329] Error: Operation must be defined in schema before it can be used.
+   ╭─[graphql:1:1]
+   │
+ 1 │ query A {
+   · ──┬──  
+   ·   ╰──── Schema doesn't have a `Query` type. You might be interested in using `@litho(url: "...")` to automatically import your existing schema. Learn more at https://litho.dev/docs/operations/import-schemas/.
+───╯
+
+
+[E0329] Error: Operation must be defined in schema before it can be used.
+   ╭─[graphql:5:1]
+   │
+ 5 │ mutation B {
+   · ────┬───  
+   ·     ╰───── Schema doesn't have a `Mutation` type. You might be interested in using `@litho(url: "...")` to automatically import your existing schema. Learn more at https://litho.dev/docs/operations/import-schemas/.
+───╯
+
+
+[E0329] Error: Operation must be defined in schema before it can be used.
+   ╭─[graphql:9:1]
+   │
+ 9 │ subscription C {
+   · ──────┬─────  
+   ·       ╰─────── Schema doesn't have a `Subscription` type. You might be interested in using `@litho(url: "...")` to automatically import your existing schema. Learn more at https://litho.dev/docs/operations/import-schemas/.
+───╯

litho-tests/tests/E0329.graphql

@@ -0,0 +1,11 @@
+query A {
+    a
+}
+
+mutation B {
+    b
+}
+
+subscription C {
+    c
+}

litho-validation/src/executable/mod.rs

@@ -33,5 +33,6 @@ where
     document.traverse(&fragments::FragmentSpreadIsPossible(database), &mut errors);
     document.traverse(&operations::OperationNameUniqueness(database), &mut errors);
     document.traverse(&operations::LoneAnonymousOperation(database), &mut errors);
+    document.traverse(&operations::SupportedOperation(database), &mut errors);
     errors
 }

litho-validation/src/executable/operations/mod.rs

@@ -1,5 +1,7 @@
 mod lone_anonymous_operation;
 mod operation_name_uniqueness;
+mod supported_operation;
 
 pub use lone_anonymous_operation::LoneAnonymousOperation;
 pub use operation_name_uniqueness::OperationNameUniqueness;
+pub use supported_operation::SupportedOperation;

litho-validation/src/executable/operations/supported_operation.rs

@@ -0,0 +1,49 @@
+use std::hash::Hash;
+use std::sync::Arc;
+
+use litho_diagnostics::Diagnostic;
+use litho_language::ast::*;
+use litho_types::Database;
+
+pub struct SupportedOperation<'a, T>(pub &'a Database<T>)
+where
+    T: Eq + Hash;
+
+impl<'a, T> Visit<'a, T> for SupportedOperation<'a, T>
+where
+    T: Eq + Hash + ToString,
+{
+    type Accumulator = Vec<Diagnostic<Span>>;
+
+    fn visit_operation_definition(
+        &self,
+        node: &'a Arc<OperationDefinition<T>>,
+        accumulator: &mut Self::Accumulator,
+    ) {
+        let Some(selection_set) = node.selection_set.ok() else {
+            return
+        };
+
+        let Some(ty) = self.0.inference.type_by_selection_set.get(selection_set) else {
+            return
+        };
+
+        if self.0.type_exists(ty) {
+            return;
+        }
+
+        let name = match node.ty.as_ref() {
+            Some(OperationType::Query(_)) | None => "Query",
+            Some(OperationType::Mutation(_)) => "Mutation",
+            Some(OperationType::Subscription(_)) => "Subscription",
+        };
+
+        accumulator.push(Diagnostic::unsupported_operation(
+            name.to_owned(),
+            node.ty
+                .as_ref()
+                .map(|ty| ty.span())
+                .unwrap_or(selection_set.span()),
+        ))
+    }
+}