Fix inline script parsing issues (#574)

Fixes #572 

The fix makes the function parser a bit more robust by round-tripping
through ast parse/unparse.

This ensures we get consistently formatted code each time and removes
any extraneous comments which were previously causing parsing issues.

Signed-off-by: Sambhav Kothari <[email protected]>

Author: sambhav

docs/examples/workflows/coinflip.md

@@ -72,12 +72,9 @@
 
             import random
 
+            result = ''heads'' if random.randint(0, 1) == 0 else ''tails''
 
-            result = "heads" if random.randint(0, 1) == 0 else "tails"
-
-            print(result)
-
-            '
+            print(result)'
       - name: heads
         script:
           command:
@@ -89,9 +86,7 @@
 
             sys.path.append(os.getcwd())
 
-            print("it was heads")
-
-            '
+            print(''it was heads'')'
       - name: tails
         script:
           command:
@@ -103,8 +98,6 @@
 
             sys.path.append(os.getcwd())
 
-            print("it was tails")
-
-            '
+            print(''it was tails'')'
     ```
 

docs/examples/workflows/complex_deps.md

@@ -78,6 +78,6 @@
           image: python:3.8
           source: "import os\nimport sys\nsys.path.append(os.getcwd())\nimport json\n\
             try: p = json.loads(r'''{{inputs.parameters.p}}''')\nexcept: p = r'''{{inputs.parameters.p}}'''\n\
-            \nif p < 0.5:\n    raise Exception(p)\nprint(42)\n"
+            \nif p < 0.5:\n    raise Exception(p)\nprint(42)"
     ```
 

docs/examples/workflows/dag-with-script-output-param-passing.md

@@ -68,8 +68,8 @@
           command:
           - python
           image: python:3.8
-          source: "import os\nimport sys\nsys.path.append(os.getcwd())\nwith open(\"/test\"\
-            , \"w\") as f_out:\n    f_out.write(\"test\")\n"
+          source: "import os\nimport sys\nsys.path.append(os.getcwd())\nwith open('/test',\
+            \ 'w') as f_out:\n    f_out.write('test')"
       - inputs:
           parameters:
           - name: a
@@ -91,8 +91,6 @@
             except: a = r''''''{{inputs.parameters.a}}''''''
 
 
-            print(a)
-
-            '
+            print(a)'
     ```
 

docs/examples/workflows/dag_conditional_parameters.md

@@ -79,25 +79,18 @@
           image: python:alpine3.6
           source: 'import random
 
-
-            print("heads" if random.randint(0, 1) == 0 else "tails")
-
-            '
+            print(''heads'' if random.randint(0, 1) == 0 else ''tails'')'
       - name: heads
         script:
           command:
           - python
           image: python:alpine3.6
-          source: 'print("heads")
-
-            '
+          source: print('heads')
       - name: tails
         script:
           command:
           - python
           image: python:alpine3.6
-          source: 'print("tails")
-
-            '
+          source: print('tails')
     ```
 

docs/examples/workflows/dag_diamond_with_callable_decorators.md

@@ -84,8 +84,6 @@
             except: message = r''''''{{inputs.parameters.message}}''''''
 
 
-            print(message)
-
-            '
+            print(message)'
     ```
 

docs/examples/workflows/dag_diamond_with_callable_script.md

@@ -70,9 +70,7 @@
             except: message = r''''''{{inputs.parameters.message}}''''''
 
 
-            print(message)
-
-            '
+            print(message)'
       - dag:
           tasks:
           - arguments:

docs/examples/workflows/dag_with_script_param_passing.md

@@ -61,9 +61,7 @@
 
             sys.path.append(os.getcwd())
 
-            print(42)
-
-            '
+            print(42)'
       - inputs:
           parameters:
           - name: a
@@ -85,8 +83,6 @@
             except: a = r''''''{{inputs.parameters.a}}''''''
 
 
-            print(a)
-
-            '
+            print(a)'
     ```
 

docs/examples/workflows/dynamic_volumes.md

@@ -51,10 +51,7 @@
 
             import subprocess
 
-
-            print(subprocess.run("cd && /mnt && df -h", shell=True, capture_output=True).stdout.decode())
-
-            '
+            print(subprocess.run(''cd && /mnt && df -h'', shell=True, capture_output=True).stdout.decode())'
           volumeMounts:
           - mountPath: /mnt/vol
             name: v

docs/examples/workflows/global_config.md

@@ -57,8 +57,6 @@
 
             sys.path.append(os.getcwd())
 
-            print("hello")
-
-            '
+            print(''hello'')'
     ```
 

docs/examples/workflows/multi_env.md

@@ -61,15 +61,10 @@
 
             import os
 
+            assert os.environ[''a''] == ''1'', os.environ[''a'']
 
-            # note that env params come in as strings
+            assert os.environ[''b''] == ''2'', os.environ[''b'']
 
-            assert os.environ["a"] == "1", os.environ["a"]
-
-            assert os.environ["b"] == "2", os.environ["b"]
-
-            assert os.environ["c"] == "3", os.environ["c"]
-
-            '
+            assert os.environ[''c''] == ''3'', os.environ[''c'']'
     ```