dev_container: Parse env vars and docker labels with `=` in values correctly (#53134)

Peter Siegel created 5 days ago

Fixes a parsing issue where docker env var key/value pairs can contain
an "=" character in the value. This is pretty common and present in all
[nvidia/cuda](https://hub.docker.com/r/nvidia/cuda) docker images. Also
adds some tests for env var parsing.

Self-Review Checklist:

- [x] I've reviewed my own diff for quality, security, and reliability
- [x] Unsafe blocks (if any) have justifying comments
- [x] The content is consistent with the [UI/UX
checklist](https://github.com/zed-industries/zed/blob/main/CONTRIBUTING.md#uiux-checklist)
- [x] Tests cover the new/changed behavior
- [x] Performance impact has been considered and is acceptable

Release Notes:

- Fixed a parsing failure where docker env var key/value pairs can
contain an "=" character in the value.

Change summary

crates/dev_container/src/docker.rs | 57 +++++++++++++++++++++++++------
1 file changed, 46 insertions(+), 11 deletions(-)

Detailed changes

crates/dev_container/src/docker.rs

@@ -56,12 +56,11 @@ impl DockerInspectConfig {
     pub(crate) fn env_as_map(&self) -> Result<HashMap<String, String>, DevContainerError> {
         let mut map = HashMap::new();
         for env_var in &self.env {
-            let parts: Vec<&str> = env_var.split("=").collect();
-            if parts.len() != 2 {
-                log::error!("Unable to parse {env_var} into and environment key-value");
+            let Some((key, value)) = env_var.split_once('=') else {
+                log::error!("Unable to parse {env_var} into an environment key-value");
                 return Err(DevContainerError::DevContainerParseFailed);
-            }
-            map.insert(parts[0].to_string(), parts[1].to_string());
+            };
+            map.insert(key.to_string(), value.to_string());
         }
         Ok(map)
     }
@@ -428,12 +427,8 @@ where
                 values
                     .iter()
                     .filter_map(|v| {
-                        let parts: Vec<&str> = v.split("=").collect();
-                        if parts.len() != 2 {
-                            None
-                        } else {
-                            Some((parts[0].to_string(), parts[1].to_string()))
-                        }
+                        let (key, value) = v.split_once('=')?;
+                        Some((key.to_string(), value.to_string()))
                     })
                     .collect(),
             ))
@@ -547,6 +542,46 @@ mod test {
         },
     };
 
+    #[test]
+    fn should_parse_simple_env_var() {
+        let config = super::DockerInspectConfig {
+            labels: super::DockerConfigLabels { metadata: None },
+            image_user: None,
+            env: vec!["KEY=value".to_string()],
+        };
+
+        let map = config.env_as_map().unwrap();
+        assert_eq!(map.get("KEY").unwrap(), "value");
+    }
+
+    #[test]
+    fn should_parse_env_var_with_equals_in_value() {
+        let config = super::DockerInspectConfig {
+            labels: super::DockerConfigLabels { metadata: None },
+            image_user: None,
+            env: vec!["COMPLEX=key=val other>=1.0".to_string()],
+        };
+
+        let map = config.env_as_map().unwrap();
+        assert_eq!(map.get("COMPLEX").unwrap(), "key=val other>=1.0");
+    }
+
+    #[test]
+    fn should_parse_simple_label() {
+        let json = r#"{"volumes": [], "labels": ["com.example.key=value"]}"#;
+        let service: DockerComposeService = serde_json_lenient::from_str(json).unwrap();
+        let labels = service.labels.unwrap();
+        assert_eq!(labels.get("com.example.key").unwrap(), "value");
+    }
+
+    #[test]
+    fn should_parse_label_with_equals_in_value() {
+        let json = r#"{"volumes": [], "labels": ["com.example.key=value=with=equals"]}"#;
+        let service: DockerComposeService = serde_json_lenient::from_str(json).unwrap();
+        let labels = service.labels.unwrap();
+        assert_eq!(labels.get("com.example.key").unwrap(), "value=with=equals");
+    }
+
     #[test]
     fn should_create_docker_inspect_command() {
         let docker = Docker::new("docker");