Add location() method to SourceSpan struct

A SourceSpan contains up to two SourceLocations: the location of the
span in the parsed source file (called in_merged), and the location of
the span in an original source file as per a path comment in the parsed
source file (called in_source). In places where only one location can
be reported, the in_source location is preferred but is not guaranteed
to exist, so the in_merged location is used as a fallback.

Because this pattern is used in multiple places, it was added as a
method to SourceSpan and all occurrences of the pattern were replaced
with a method call.

3 files changed, 11 insertions, 10 deletions

diff --git a/src/locators/source.rs b/src/locators/source.rs
index 2f10bd9..20542e3 100644
--- a/src/locators/source.rs
+++ b/src/locators/source.rs
@@ -11,6 +11,12 @@ pub struct SourceSpan {
     pub in_source: Option<SourceLocation>,
 }
 
+impl SourceSpan {
+    pub fn location(&self) -> &SourceLocation {
+        self.in_source.as_ref().unwrap_or(&self.in_merged)
+    }
+}
+
 
 #[derive(Clone)]
 pub struct SourceLocation {
diff --git a/src/print.rs b/src/print.rs
index 0c81c07..b2c2ba8 100644
--- a/src/print.rs
+++ b/src/print.rs
@@ -71,14 +71,10 @@ fn get_message_for_semantic_error(error: &SemanticParseError) -> String {
             format!("Block was not closed, add a '}}' character to close"),
         SemErr::UndefinedSymbol(name) =>
             format!("Undefined symbol, no label or macro has been defined with the name '{name}'"),
-        SemErr::RedefinedSymbol((_, source)) => {
-            let location = source.in_source.as_ref().unwrap_or(&source.in_merged);
-            format!("Redefined symbol, first defined at {location}")
-        }
-        SemErr::MacroInvocationBeforeDefinition((_, source)) => {
-            let location = source.in_source.as_ref().unwrap_or(&source.in_merged);
-            format!("Macro used before definition, definition is at {location}")
-        }
+        SemErr::RedefinedSymbol((_, source)) =>
+            format!("Redefined symbol, first defined at {}", source.location()),
+        SemErr::MacroInvocationBeforeDefinition((_, source)) =>
+            format!("Macro used before definition, definition is at {}", source.location()),
         SemErr:: SyntaxError(syntax_error) => match syntax_error {
             SynErr::UnterminatedComment =>
                 format!("Unclosed comment, add a ')' character to close"),
diff --git a/src/translators/symbols_generator.rs b/src/translators/symbols_generator.rs
index 6db1d46..d30facd 100644
--- a/src/translators/symbols_generator.rs
+++ b/src/translators/symbols_generator.rs
@@ -11,8 +11,7 @@ pub fn generate_symbols_file(semantic_tokens: &[SemanticToken]) -> String {
             let address = token.bytecode.location.address;
             if address > 0xffff { break; }
             let name = &definition.name;
-            let location = token.source.in_source.as_ref()
-                .unwrap_or(&token.source.in_merged);
+            let location = token.source.location();
             symbols.push_str(&format!("{address:04x} {name} {location}\n"));
         }
     }