From 1d6291b9ba1d8a183cf816a80f17f14a0b4ee7ff Mon Sep 17 00:00:00 2001
From: David Mak <csdavidmak@ust.hk>
Date: Tue, 14 Nov 2023 18:43:08 +0800
Subject: [PATCH] ast: Add Ord implementation to Location

---
 nac3ast/src/location.rs | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/nac3ast/src/location.rs b/nac3ast/src/location.rs
index 2d658d5b7..976dbf055 100644
--- a/nac3ast/src/location.rs
+++ b/nac3ast/src/location.rs
@@ -1,8 +1,9 @@
 //! Datatypes to support source location information.
+use std::cmp::Ordering;
 use crate::ast_gen::StrRef;
 use std::fmt;
 
-#[derive(Clone, Copy, Debug, PartialEq)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub struct FileName(pub StrRef);
 impl Default for FileName {
     fn default() -> Self {
@@ -17,7 +18,7 @@ impl From<String> for FileName {
 }
 
 /// A location somewhere in the sourcecode.
-#[derive(Clone, Copy, Debug, Default, PartialEq)]
+#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
 pub struct Location {
     pub row: usize,
     pub column: usize,
@@ -30,6 +31,28 @@ impl fmt::Display for Location {
     }
 }
 
+impl Ord for Location {
+    fn cmp(&self, other: &Self) -> Ordering {
+        let file_cmp = self.file.0.to_string().cmp(&other.file.0.to_string());
+        if file_cmp != Ordering::Equal {
+            return file_cmp
+        }
+
+        let row_cmp = self.row.cmp(&other.row);
+        if row_cmp != Ordering::Equal {
+            return row_cmp
+        }
+
+        self.column.cmp(&other.column)
+    }
+}
+
+impl PartialOrd for Location {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
 impl Location {
     pub fn visualize<'a>(
         &self,