cse15l-lab-reports
Debugging
Understanding the relationship between bugs and symptoms
Example 1: Testing MarkdownParse get links method using an image reference
Prompt: “Write a program that takes a markdown file as a command line argument and then prints out all of the URLs of the links (but not of images) in that file.”
Goal: to fix the code in MarkdownParse so that there is no error and the image reference is not added to the list of links
link to failure-inducing test case file
BUG: the original code does not account for image refrences.
note there are many other bugs, but this test focuses on just one of them
SYMPTOM: infinite loop (crashes then loads a OutOfMemory error)
The symptom of the infinte loop gives a hint of where to look for the bug in the code. In this case there is a bug in the while loop. Additonally it is important to understand the failure-inducing test case, then what the desired output is (according to prompt images should not printed; therefore [] should be the output). Now there is sufficent information to debug.
Code added in while loop to account for image reference
Example 2: Testing MarkdownParse get links method with an improper formatting for creating a link
Prompt: “Write a program that takes a markdown file as a command line argument and then prints out all of the URLs of the links (but not of images) in that file.”
Goal: to fix the code in MarkdownParse so that the link gets added to the list and gets printed out regardless of the incorrect format (assuming the link is correct)
link to failure-inducing test case file
BUG: the initial code does not account for incorrect formatting when creating a link. There are multiple possibilites, but one focus is a space between the [] & ()
note there are many other bugs, but this test focuses on just one of them
SYMPTOM: infinite loop (crashes then loads a OutOfMemory error)
Similar to the first example, the symptom is an infinite loop and the bug can be found in the while loop; However, the bug is a little different from the first example, and the goal is also different. Fixing the bug as a very similar process, but this time the link should be printed out. It should look something like this: [https://something.com)]
Code added in while loop to print correct link regardless of basic formatting error
Example 3: Testing MarkdownParse get links method with no link
Prompt: “Write a program that takes a markdown file as a command line argument and then prints out all of the URLs of the links (but not of images) in that file.”
Goal: to fix the code in MarkdownParse so that there is no error and the list prints an empty list []
link to failure-inducing test case file
BUG: the initial code does not account when there is no link provided.
note there are many other bugs, but this test focuses on just one of them
SYMPTOM: infinite loop (crashes then loads a OutOfMemory error)
Although the bug, symptom and the expected output for this example and the first one is similar, the failure-inducing tests are different and the code added for the first example failed to address the bug in this example. based on the symptom there is a bug in the while loop, but there is a different issue with the code.
Code added in while loop to print empty list without causing an infinite loop.
