The special filename '-' can be used to indicate that input should be read from STDIN instead. This PR also adds a new test for this feature in TestCommandTest. Since this added to the code duplication in TestCommandTest, this PR adds a new method to remove some duplicated code and thus make the tests clearer.
I was in two minds about whether to keep 0248dc8 in this PR or to separate it into its own PR. Let me know if you'd prefer me to separate it!
The special filename '-' can be used to indicate that input should be read from STDIN instead. This PR also adds a new test for this feature in TestCommandTest. Since this added to the code duplication in TestCommandTest, this PR adds a new method to remove some duplicated code and thus make the tests clearer.
I was in two minds about whether to keep 0248dc8 in this PR or to separate it into its own PR. Let me know if you'd prefer me to separate it!