compiler, cli: Support Nice Compilation Error Messages

Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
2026-05-22 02:37:33 -04:00
parent 5845cb75cc
commit e53c32f802
9 changed files with 115 additions and 4 deletions
@@ -210,6 +210,33 @@ public struct SourceCode {
    return self.code
  }

+  public func getSourceSnippet(
+    location: SourceLocation, context: Int = 0
+  ) -> (FilePath, String, String, String)? {
+    guard let path = self.pathForLocation(location.range.lowerBound) else {
+      return .none
+    }
+    let lower = String.UTF8View.Index(utf16Offset: location.range.lowerBound, in: self.code)
+    let upper = String.UTF8View.Index(utf16Offset: location.range.upperBound, in: self.code)
+    let prior_start =
+      if location.range.lowerBound - context >= 0 {
+        String.UTF8View.Index(utf16Offset: location.range.lowerBound - context, in: self.code)
+      } else {
+        String.UTF8View.Index(utf16Offset: location.range.lowerBound, in: self.code)
+      }
+    let after_end =
+      if location.range.upperBound + context < self.code.count {
+        String.UTF8View.Index(utf16Offset: location.range.upperBound + context, in: self.code)
+      } else {
+        String.UTF8View.Index(utf16Offset: location.range.upperBound, in: self.code)
+      }
+
+    let result = String(self.code.utf16[lower..<upper])!
+    let prior = String(self.code.utf16[prior_start..<lower])!
+    let after = String(self.code.utf16[upper...after_end])!
+    return (path, result, prior, after)
+  }
+
  public func getLocations() -> FileSourceLocation {
    return self.locations
  }