Suggest accessing field if method doesn't exist (#2977)

crates/typst/src/eval/call.rs

@@ -1,5 +1,5 @@
 use comemo::{Prehashed, Tracked, TrackedMut};
-use ecow::EcoVec;
+use ecow::{eco_format, EcoVec};
 
 use crate::diag::{bail, error, At, HintedStrResult, SourceResult, Trace, Tracepoint};
 use crate::engine::Engine;
@@ -99,13 +99,27 @@ impl Eval for ast::FuncCall<'_> {
                     field.as_str()
                 );
 
-                if let Value::Dict(dict) = target {
+                let mut field_hint = || {
-                    if matches!(dict.get(&field), Ok(Value::Func(_))) {
+                    if target.field(&field).is_ok() {
-                        error.hint(
+                        error.hint(eco_format!(
-                            "to call the function stored in the dictionary, \
+                            "did you mean to access the field `{}`?",
-                             surround the field access with parentheses",
+                            field.as_str()
-                        );
+                        ));
                     }
+                };
+
+                match target {
+                    Value::Dict(ref dict) => {
+                        if matches!(dict.get(&field), Ok(Value::Func(_))) {
+                            error.hint(
+                                "to call the function stored in the dictionary, \
+                             surround the field access with parentheses",
+                            );
+                        } else {
+                            field_hint();
+                        }
+                    }
+                    _ => field_hint(),
                 }
 
                 bail!(error);

tests/typ/compiler/dict.typ

@@ -119,6 +119,7 @@
   )
 
   // Error: 8-15 type dictionary has no method `nonfunc`
+  // Hint: 8-15 did you mean to access the field `nonfunc`?
   dict.nonfunc()
 }
 

tests/typ/compiler/methods.typ

@@ -35,6 +35,12 @@
 #let numbers = ()
 #numbers.fun()
 
+---
+// Error: 2:4-2:10 type content has no method `stroke`
+// Hint: 2:4-2:10 did you mean to access the field `stroke`?
+#let l = line(stroke: red)
+#l.stroke()
+
 ---
 // Error: 2:2-2:43 cannot mutate a temporary value
 #let numbers = (1, 2, 3)