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Software Engineering vocabulary · Testing

Edge case

Meaning in software engineering, with examples

/ˈedʒ keɪs/nounCore term

In software engineering, edge case means: An unusual situation at the limits of what a program expects, such as an empty list, a very long name or a date like 29 February.

In Turkish: uç durum, sınır durumu, istisnai durum

How it is used

Very common in code reviews and planning: 'What about the edge case where the list is empty?' Developers handle, cover, miss and test edge cases.

Example sentences

  1. Did you handle the edge case where the user has no orders yet?

  2. Most of our production bugs come from edge cases we didn't test.

Common collocations

  • handle an edge case
  • cover edge cases
  • miss an edge case
  • test edge cases
  • test caseOne specific situation you check, with set inputs, steps and an expected result, for example 'logging in with a wrong password shows an error'.
  • unit testA small automated test that checks one function or class on its own, separate from the database, the network and the rest of the system.
  • bugA mistake in a program that makes it behave in a way nobody intended, such as showing wrong results, freezing or closing suddenly.
  • regressionA bug where something that used to work stops working after a change, such as a new feature breaking an old one.

This word in other fields

The same English word can have a different meaning in another field:

More terms: Testing

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