Start fixing error outputs

Signed-off-by: Marcel Müller <neikos@neikos.email>

tests/file_tests.rs

@@ -1,3 +1,5 @@
+#![allow(missing_docs)]
+
 use std::collections::HashMap;
 use std::path::Path;
 
@@ -6,6 +8,8 @@ use nomo::functions::FunctionMap;
 
 test_each_file::test_each_path! { for ["nomo"] in "./tests/cases/" as cases => check_for_input }
 
+test_each_file::test_each_path! { for ["nomo"] in "./tests/errors/" as error_cases => check_errors }
+
 #[derive(serde::Serialize)]
 struct Info {
     input: String,
@@ -63,3 +67,67 @@ fn check_for_input([path]: [&Path; 1]) {
 
     insta::assert_debug_snapshot!(format!("{basename}.4-output"), output);
 }
+
+fn check_errors([path]: [&Path; 1]) {
+    let mut settings = insta::Settings::clone_current();
+    settings.set_snapshot_path("errors");
+    settings.set_prepend_module_to_snapshot(false);
+
+    let basename = path.file_stem().unwrap().to_string_lossy();
+    let input = std::fs::read_to_string(path).unwrap();
+
+    let (context, input) = input.split_once("\n---\n").unwrap_or_else(|| ("", &input));
+
+    let map = if !context.is_empty() {
+        serde_json::from_str::<HashMap<String, serde_json::Value>>(context).unwrap()
+    } else {
+        HashMap::new()
+    };
+
+    settings.set_info(&Info {
+        input: input.to_string(),
+        context: map.clone(),
+    });
+
+    let mut context = Context::new();
+
+    for (k, v) in map {
+        context.try_insert(k, v).unwrap();
+    }
+
+    let _guard = settings.bind_to_scope();
+
+    let parsed = nomo::lexer::parse(input.into()).map_err(|err| err.to_report());
+
+    match &parsed {
+        Ok(parsed) => insta::assert_debug_snapshot!(format!("{basename}.1-parsed"), parsed),
+        Err(parsed) => insta::assert_snapshot!(format!("{basename}.1-parsed"), parsed),
+    }
+
+    let Ok(parsed) = parsed else {
+        return;
+    };
+
+    let ast = nomo::parser::parse(parsed.tokens()).map_err(|err| err.to_report(input));
+
+    match &ast {
+        Ok(ast) => insta::assert_debug_snapshot!(format!("{basename}.2-ast"), ast),
+        Err(ast) => insta::assert_snapshot!(format!("{basename}.2-ast"), ast),
+    }
+
+    let Ok(ast) = ast else {
+        return;
+    };
+
+    let emit = nomo::compiler::emit_machine(ast);
+
+    insta::assert_debug_snapshot!(format!("{basename}.3-instructions"), emit);
+
+    let output = nomo::eval::execute(&FunctionMap::default(), &emit, &context)
+        .map_err(|err| err.to_string());
+
+    match &output {
+        Ok(output) => insta::assert_debug_snapshot!(format!("{basename}.4-output"), output),
+        Err(output) => insta::assert_snapshot!(format!("{basename}.4-output"), output),
+    }
+}