Use try/except to catch error

src/aiidalab_qe/setup/codes.py

@@ -1,3 +1,4 @@
+import json
 import subprocess
 from pathlib import Path
 from shutil import which
@@ -44,18 +45,48 @@ def get_qe_env():
 
 
 def qe_installed():
-    import json
+    """Check if Quantum Espresso (QE) is installed in the specified conda environment.
 
-    env_exist = get_qe_env().exists()
-    proc = subprocess.run(
-        ["conda", "list", "-n", f"{get_qe_env().name}", "--json", "--full-name", "qe"],
-        check=True,
-        capture_output=True,
-    )
+    Returns:
+        bool: True if the environment exists and QE is installed; False otherwise.
+    """
+    try:
+        # Verify if the specified conda environment exists
+        env_exist = get_qe_env().exists()
+
+        if not env_exist:
+            return False
+
+        # Run the conda list command to check for the QE package
+        proc = subprocess.run(
+            [
+                "conda",
+                "list",
+                "-n",
+                f"{get_qe_env().name}",
+                "--json",
+                "--full-name",
+                "qe",
+            ],
+            check=True,
+            capture_output=True,
+        )
+
+        # Load and interpret the JSON output
+        info = json.loads(proc.stdout.decode())
 
-    info = json.loads(str(proc.stdout.decode()))[0]
+        # Check if 'qe' is listed in the environment
+        for package in info:
+            if package.get("name") == "qe":
+                return True
+        return False  # noqa: TRY300
 
-    return env_exist and "qe" == info["name"]
+    except subprocess.CalledProcessError:
+        # Handle cases where the conda list command fails
+        return False
+    except (json.JSONDecodeError, IndexError):
+        # Handle cases where the JSON output is invalid or missing expected data
+        return False
 
 
 def install_qe():