feat: add snapshot tests for compiler errors

Verify good compiler error output by creating several snapshot tests.
Also, slightly improve some of the messages.

Justfile

@@ -19,6 +19,13 @@ check:
 fmt:
   cargo +nightly fmt --all
 
+# Run snapshot tests and review any updates
+snapshots:
+  cargo insta test --workspace --all-features \
+    --test-runner nextest \
+    --unreferenced delete \
+    --review
+
 # Start up the local server for the book
 @book:
   cd book && just dev

crates/stef-cli/Cargo.toml

@@ -14,7 +14,7 @@ name = "stef"
 path = "src/main.rs"
 
 [dependencies]
-clap = { version = "4.4.6", features = ["derive", "wrap_help"] }
+clap = { version = "4.4.7", features = ["derive", "wrap_help"] }
 color-eyre.workspace = true
 glob.workspace = true
 miette = { workspace = true, features = ["fancy-no-backtrace"] }

crates/stef-compiler/Cargo.toml

@@ -13,3 +13,7 @@ license.workspace = true
 miette.workspace = true
 stef-parser = { path = "../stef-parser" }
 thiserror.workspace = true
+
+[dev-dependencies]
+insta.workspace = true
+miette = { workspace = true, features = ["fancy-no-backtrace"] }

crates/stef-compiler/src/ids.rs

@@ -40,7 +40,7 @@ pub enum DuplicateFieldId {
         #[label("used here again")]
         second: Range<usize>,
     },
-    #[error("duplicate ID {} in field {position}, already used in {other_position}", id.get())]
+    #[error("duplicate ID {} in position {position}, already used at {other_position}", id.get())]
     #[diagnostic(help("the IDs for each field must be unique"))]
     Unnamed {
         id: Id,
@@ -116,8 +116,8 @@ fn validate_field_ids(value: &Fields<'_>) -> Result<(), DuplicateFieldId> {
                     visited.insert(field.id.get(), (pos, field.id.span())).map(
                         |(other_position, other_span)| DuplicateFieldId::Unnamed {
                             id: field.id.clone(),
-                            position: pos,
-                            other_position,
+                            position: pos + 1,
+                            other_position: other_position + 1,
                             first: other_span.into(),
                             second: field.id.span().into(),
                         },

crates/stef-compiler/tests/compiler.rs

@@ -0,0 +1,43 @@
+use std::{
+    fmt::{self, Display},
+    fs,
+};
+
+use insta::{assert_snapshot, glob};
+use miette::{Diagnostic, MietteHandler, MietteHandlerOpts, NamedSource, Report, ReportHandler};
+use stef_parser::Schema;
+
+#[test]
+fn compile_invalid_schema() {
+    struct Wrapper<'a>(&'a MietteHandler, &'a dyn Diagnostic);
+
+    impl<'a> Display for Wrapper<'a> {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            self.0.debug(self.1, f)
+        }
+    }
+
+    let handler = MietteHandlerOpts::new()
+        .color(false)
+        .context_lines(3)
+        .force_graphical(true)
+        .terminal_links(false)
+        .width(120)
+        .build();
+
+    glob!("inputs/invalid/*.stef", |path| {
+        let input = fs::read_to_string(path).unwrap();
+        let schema = Schema::parse(input.as_str()).unwrap();
+        let result = stef_compiler::validate_schema(&schema).unwrap_err();
+        let report = Report::new(result).with_source_code(NamedSource::new(
+            path.file_name().unwrap().to_string_lossy(),
+            input,
+        ));
+
+        assert_snapshot!(
+            "error",
+            Wrapper(&handler, &*report).to_string(),
+            stringify!(stef_compiler::validate_schema(&schema).unwrap_err())
+        );
+    });
+}

crates/stef-compiler/tests/inputs/invalid/enum_gen_dup.stef

@@ -0,0 +1,4 @@
+enum Sample<T, T> {
+    One @1,
+    Two { value: T @1 } @2,
+}

crates/stef-compiler/tests/inputs/invalid/enum_gen_unused.stef

@@ -0,0 +1,4 @@
+enum Sample<T> {
+    One @1,
+    Two { value: string @1 } @2,
+}

crates/stef-compiler/tests/inputs/invalid/enum_named_dup_id.stef

@@ -0,0 +1,7 @@
+enum Sample {
+    One @1,
+    Two {
+        field1: string @1,
+        field2: string @1,
+    } @2,
+}

crates/stef-compiler/tests/inputs/invalid/enum_named_dup_name.stef

@@ -0,0 +1,7 @@
+enum Sample {
+    One @1,
+    Two {
+        field: string @1,
+        field: string @2,
+    } @2,
+}

crates/stef-compiler/tests/inputs/invalid/enum_unnamed_dup_id.stef

@@ -0,0 +1,4 @@
+enum Sample {
+    One @1,
+    Two(string @1, string @1) @2,
+}

crates/stef-compiler/tests/inputs/invalid/enum_variant_dup_id.stef

@@ -0,0 +1,4 @@
+enum Sample {
+    One @1,
+    Two @1,
+}

crates/stef-compiler/tests/inputs/invalid/enum_variant_dup_name.stef

@@ -0,0 +1,4 @@
+enum Sample {
+    One @1,
+    One @2,
+}

crates/stef-compiler/tests/inputs/invalid/struct_gen_dup.stef

@@ -0,0 +1,3 @@
+struct Sample<T, T> {
+    value: T @1,
+}

crates/stef-compiler/tests/inputs/invalid/struct_gen_unused.stef

@@ -0,0 +1,3 @@
+struct Sample<T> {
+    value: string @1,
+}

crates/stef-compiler/tests/inputs/invalid/struct_named_dup_id.stef

@@ -0,0 +1,4 @@
+struct Sample {
+    field1: string @1,
+    field2: string @1,
+}

crates/stef-compiler/tests/inputs/invalid/struct_named_dup_name.stef

@@ -0,0 +1,4 @@
+struct Sample {
+    field: string @1,
+    field: string @2,
+}

crates/stef-compiler/tests/inputs/invalid/struct_unnamed_dup_id.stef

@@ -0,0 +1 @@
+struct Sample(string @1, string @1)

crates/stef-compiler/tests/snapshots/compiler__error@enum_gen_dup.stef.snap

@@ -0,0 +1,19 @@
+---
+source: crates/stef-compiler/tests/compiler.rs
+expression: "stef_compiler :: validate_schema(& schema).unwrap_err()"
+input_file: crates/stef-compiler/tests/inputs/invalid/enum_gen_dup.stef
+---
+  × invalid generic type found
+  ├─▶ duplicate generic type name found
+  ╰─▶ duplicate generic type name `T`
+   ╭─[enum_gen_dup.stef:1:1]
+ 1 │ enum Sample<T, T> {
+   ·             ┬  ┬
+   ·             │  ╰── used here again
+   ·             ╰── first declared here
+ 2 │     One @1,
+ 3 │     Two { value: T @1 } @2,
+ 4 │ }
+   ╰────
+  help: the names of each generic type must be unique
+

crates/stef-compiler/tests/snapshots/compiler__error@enum_gen_unused.stef.snap

@@ -0,0 +1,18 @@
+---
+source: crates/stef-compiler/tests/compiler.rs
+expression: "stef_compiler :: validate_schema(& schema).unwrap_err()"
+input_file: crates/stef-compiler/tests/inputs/invalid/enum_gen_unused.stef
+---
+  × invalid generic type found
+  ├─▶ unused generic type argument found
+  ╰─▶ unused generic type argument `T`
+   ╭─[enum_gen_unused.stef:1:1]
+ 1 │ enum Sample<T> {
+   ·             ┬
+   ·             ╰── declared here
+ 2 │     One @1,
+ 3 │     Two { value: string @1 } @2,
+ 4 │ }
+   ╰────
+  help: each declared generic must be used in some way
+

crates/stef-compiler/tests/snapshots/compiler__error@enum_named_dup_id.stef.snap

@@ -0,0 +1,23 @@
+---
+source: crates/stef-compiler/tests/compiler.rs
+expression: "stef_compiler :: validate_schema(& schema).unwrap_err()"
+input_file: crates/stef-compiler/tests/inputs/invalid/enum_named_dup_id.stef
+---
+  × duplicate ID found
+  ├─▶ duplicate ID in a field
+  ╰─▶ duplicate ID 1 in field `field2`, already used in `field1`
+   ╭─[enum_named_dup_id.stef:1:1]
+ 1 │ enum Sample {
+ 2 │     One @1,
+ 3 │     Two {
+ 4 │         field1: string @1,
+   ·                        ─┬
+   ·                         ╰── first declared here
+ 5 │         field2: string @1,
+   ·                        ─┬
+   ·                         ╰── used here again
+ 6 │     } @2,
+ 7 │ }
+   ╰────
+  help: the IDs for each field must be unique
+

crates/stef-compiler/tests/snapshots/compiler__error@enum_named_dup_name.stef.snap

@@ -0,0 +1,23 @@
+---
+source: crates/stef-compiler/tests/compiler.rs
+expression: "stef_compiler :: validate_schema(& schema).unwrap_err()"
+input_file: crates/stef-compiler/tests/inputs/invalid/enum_named_dup_name.stef
+---
+  × duplicate name found
+  ├─▶ duplicate name in a field
+  ╰─▶ duplicate field name `field`
+   ╭─[enum_named_dup_name.stef:1:1]
+ 1 │ enum Sample {
+ 2 │     One @1,
+ 3 │     Two {
+ 4 │         field: string @1,
+   ·         ──┬──
+   ·           ╰── first declared here
+ 5 │         field: string @2,
+   ·         ──┬──
+   ·           ╰── used here again
+ 6 │     } @2,
+ 7 │ }
+   ╰────
+  help: the names of each field must be unique
+

crates/stef-compiler/tests/snapshots/compiler__error@enum_unnamed_dup_id.stef.snap

@@ -0,0 +1,19 @@
+---
+source: crates/stef-compiler/tests/compiler.rs
+expression: "stef_compiler :: validate_schema(& schema).unwrap_err()"
+input_file: crates/stef-compiler/tests/inputs/invalid/enum_unnamed_dup_id.stef
+---
+  × duplicate ID found
+  ├─▶ duplicate ID in a field
+  ╰─▶ duplicate ID 1 in position 2, already used at 1
+   ╭─[enum_unnamed_dup_id.stef:1:1]
+ 1 │ enum Sample {
+ 2 │     One @1,
+ 3 │     Two(string @1, string @1) @2,
+   ·                ─┬         ─┬
+   ·                 │          ╰── used here again
+   ·                 ╰── first declared here
+ 4 │ }
+   ╰────
+  help: the IDs for each field must be unique
+

crates/stef-compiler/tests/snapshots/compiler__error@enum_variant_dup_id.stef.snap

@@ -0,0 +1,20 @@
+---
+source: crates/stef-compiler/tests/compiler.rs
+expression: "stef_compiler :: validate_schema(& schema).unwrap_err()"
+input_file: crates/stef-compiler/tests/inputs/invalid/enum_variant_dup_id.stef
+---
+  × duplicate ID found
+  ├─▶ duplicate ID in an enum variant
+  ╰─▶ duplicate ID 1 in enum variant `Two`, already used in `One`
+   ╭─[enum_variant_dup_id.stef:1:1]
+ 1 │ enum Sample {
+ 2 │     One @1,
+   ·         ─┬
+   ·          ╰── first declared here
+ 3 │     Two @1,
+   ·         ─┬
+   ·          ╰── used here again
+ 4 │ }
+   ╰────
+  help: the IDs for each variant of an enum must be unique
+

crates/stef-compiler/tests/snapshots/compiler__error@enum_variant_dup_name.stef.snap

@@ -0,0 +1,20 @@
+---
+source: crates/stef-compiler/tests/compiler.rs
+expression: "stef_compiler :: validate_schema(& schema).unwrap_err()"
+input_file: crates/stef-compiler/tests/inputs/invalid/enum_variant_dup_name.stef
+---
+  × duplicate name found
+  ├─▶ duplicate name in an enum variant
+  ╰─▶ duplicate variant name `One` in enum
+   ╭─[enum_variant_dup_name.stef:1:1]
+ 1 │ enum Sample {
+ 2 │     One @1,
+   ·     ─┬─
+   ·      ╰── first declared here
+ 3 │     One @2,
+   ·     ─┬─
+   ·      ╰── used here again
+ 4 │ }
+   ╰────
+  help: the names of each variant must be unique
+

crates/stef-compiler/tests/snapshots/compiler__error@struct_gen_dup.stef.snap

@@ -0,0 +1,18 @@
+---
+source: crates/stef-compiler/tests/compiler.rs
+expression: "stef_compiler :: validate_schema(& schema).unwrap_err()"
+input_file: crates/stef-compiler/tests/inputs/invalid/struct_gen_dup.stef
+---
+  × invalid generic type found
+  ├─▶ duplicate generic type name found
+  ╰─▶ duplicate generic type name `T`
+   ╭─[struct_gen_dup.stef:1:1]
+ 1 │ struct Sample<T, T> {
+   ·               ┬  ┬
+   ·               │  ╰── used here again
+   ·               ╰── first declared here
+ 2 │     value: T @1,
+ 3 │ }
+   ╰────
+  help: the names of each generic type must be unique
+

crates/stef-compiler/tests/snapshots/compiler__error@struct_gen_unused.stef.snap

@@ -0,0 +1,17 @@
+---
+source: crates/stef-compiler/tests/compiler.rs
+expression: "stef_compiler :: validate_schema(& schema).unwrap_err()"
+input_file: crates/stef-compiler/tests/inputs/invalid/struct_gen_unused.stef
+---
+  × invalid generic type found
+  ├─▶ unused generic type argument found
+  ╰─▶ unused generic type argument `T`
+   ╭─[struct_gen_unused.stef:1:1]
+ 1 │ struct Sample<T> {
+   ·               ┬
+   ·               ╰── declared here
+ 2 │     value: string @1,
+ 3 │ }
+   ╰────
+  help: each declared generic must be used in some way
+