feat(error display): better error message for unmatched "

flake.nix

@@ -4,9 +4,9 @@
     flake-utils.url = "github:numtide/flake-utils";
   };
   outputs = {
-    self,
     nixpkgs,
     flake-utils,
+    ...
   }:
     flake-utils.lib.eachDefaultSystem
     (system: let
@@ -28,6 +28,8 @@
           pkgs.bacon
           pkgs.cargo-semver-checks
           pkgs.cargo-insta
+          # debugger
+          pkgs.lldb
         ];
       };
       packages.default = pkgs.rustPlatform.buildRustPackage {

notes.org

@@ -220,7 +220,9 @@ i will use rustyline, since it seems like the most feature-complete
 
 * DONE parse strings
 
-* TODO better error message display for unclosed " in string
+* DONE better error message display for unclosed " in string
+
+* TODO print errors to stderr
 
 * TODO parse insert statements in the form
 insert <id:int> <username:string> <email:string>

src/error_display.rs

@@ -32,15 +32,34 @@ impl OSDBError for CommandParseError {
 impl OSDBError for ScanError {
     fn display(&self, file: &str, input: &str) {
         let location = (file, Into::<std::ops::Range<usize>>::into(&self.location));
-        Report::build(ReportKind::Error, location.clone())
+
-            .with_message(format!("{self}"))
+        let report =
-            .with_label(
+            Report::build(ReportKind::Error, location.clone()).with_message(format!("{self}"));
+        let report = match &self.kind {
+            crate::tokens::ScanErrorKind::UnexpectedEndOfInputWhileLookingForMatching(
+                c,
+                start_location,
+            ) => {
+                let start_location = (file, Into::<std::ops::Range<usize>>::into(start_location));
+                report
+                    .with_label(
+                        Label::new(location)
+                            .with_order(-1)
+                            .with_color(Color::Red)
+                            .with_message(format!("expected {c:?} but found end of input")),
+                    )
+                    .with_label(
+                        Label::new(start_location)
+                            .with_color(Color::Blue)
+                            .with_message(format!("looking for a {c:?} to match this")),
+                    )
+            }
+            _ => report.with_label(
                 Label::new(location)
                     .with_color(Color::Red)
                     .with_message(format!("{self}")),
-            )
+            ),
-            .finish()
+        };
-            .print((file, Source::from(input)))
+        report.finish().print((file, Source::from(input))).unwrap();
-            .unwrap();
     }
 }