Bugfix #2001 - Error instead of panic when applying malformed patches. (#2007)

Cargo.lock

@@ -1286,11 +1286,10 @@ dependencies = [
 
 [[package]]
 name = "dmp"
-version = "0.1.3"
+version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1796e147190351ab441586c68b74494b18a70b0e39fb9bf8e84e38635bf4c92a"
+checksum = "bfaa1135a34d26e5cc5b4927a8935af887d4f30a5653a797c33b9a4222beb6d9"
 dependencies = [
- "regex",
  "urlencoding",
 ]
 

lib/Cargo.toml

@@ -61,7 +61,7 @@ bung = "0.1.0"
 channel = { version = "1.8.0", package = "async-channel" }
 chrono = { version = "0.4.24", features = ["serde"] }
 derive = { version = "0.8.0", package = "surrealdb-derive" }
-dmp = "0.1.3"
+dmp = "0.2.0"
 echodb = { version = "0.4.0", optional = true }
 executor = { version = "1.5.1", package = "async-executor" }
 flume = "0.10.14"

lib/src/sql/value/diff.rs

@@ -65,9 +65,9 @@ impl Value {
 				op: Op::Change,
 				path,
 				value: {
-					let mut dmp = dmp::new();
-					let mut pch = dmp.patch_make1(a, b);
-					let txt = dmp.patch_to_text(&mut pch);
+					let dmp = dmp::new();
+					let pch = dmp.patch_make1(a, b);
+					let txt = dmp.patch_to_text(&pch);
 					txt.into()
 				},
 			}),

lib/src/sql/value/patch.rs

@@ -15,9 +15,17 @@ impl Value {
 				Op::Change => {
 					if let Value::Strand(p) = o.value {
 						if let Value::Strand(v) = self.pick(&o.path) {
-							let mut dmp = dmp::new();
-							let mut pch = dmp.patch_from_text(p.as_string());
-							let (txt, _) = dmp.patch_apply(&mut pch, v.as_str());
+							let dmp = dmp::new();
+							let mut pch = dmp.patch_from_text(p.as_string()).map_err(|e| {
+								Error::InvalidPatch {
+									message: format!("{e:?}"),
+								}
+							})?;
+							let (txt, _) = dmp.patch_apply(&mut pch, v.as_str()).map_err(|e| {
+								Error::InvalidPatch {
+									message: format!("{e:?}"),
+								}
+							})?;
 							let txt = txt.into_iter().collect::<String>();
 							self.put(&o.path, Value::from(txt));
 						}
@@ -111,4 +119,12 @@ mod tests {
 		val.patch(ops).unwrap();
 		assert_eq!(res, val);
 	}
+
+	#[tokio::test]
+	async fn patch_change_invalid() {
+		// See https://github.com/surrealdb/surrealdb/issues/2001
+		let mut val = Value::parse("{ test: { other: 'test', something: 123 }, temp: true }");
+		let ops = Value::parse("[{ op: 'change', path: '/test/other', value: 'text' }]");
+		assert!(val.patch(ops).is_err());
+	}
 }