Improve support for Python 3.6

platformio/commands/upgrade.py

@@ -53,16 +53,15 @@ def cli(dev, verbose):
         subprocess.run(
             [python_exe, "-m", "pip", "install", "--upgrade", pkg_spec],
             check=True,
-            capture_output=not verbose,
+            stdout=subprocess.PIPE if not verbose else None,
         )
-        r = subprocess.run(
+        output = subprocess.run(
             [python_exe, "-m", "platformio", "--version"],
             check=True,
-            capture_output=True,
-            text=True,
-        )
-        assert "version" in r.stdout
-        actual_version = r.stdout.split("version", 1)[1].strip()
+            stdout=subprocess.PIPE,
+        ).stdout.decode()
+        assert "version" in output
+        actual_version = output.split("version", 1)[1].strip()
         click.secho(
             "PlatformIO has been successfully upgraded to %s" % actual_version,
             fg="green",

platformio/system/completion.py

@@ -29,8 +29,10 @@ class ShellType(Enum):
 
 
 def get_bash_version():
-    result = subprocess.run(["bash", "--version"], capture_output=True, check=True)
-    match = re.search(r"version\s+(\d+)\.(\d+)", result.stdout.decode(), re.IGNORECASE)
+    output = subprocess.run(
+        ["bash", "--version"], check=True, stdout=subprocess.PIPE
+    ).stdout.decode()
+    match = re.search(r"version\s+(\d+)\.(\d+)", output, re.IGNORECASE)
     if match:
         return (int(match.group(1)), int(match.group(2)))
     return (0, 0)