Support failed not (!) tests (#59)

README.md

@@ -52,7 +52,7 @@ Tests are defined with the `@test` function. Each test begins with a description
 @<a href=#writing-tests>test</a> <i>description</i> [<i>actual</i>] <a href=https://fishshell.com/docs/current/cmds/test.html#operators-for-files-and-directories>operator</a> <i>expected</i>
 </pre>
 
-> Operators to combine expressions are not currently supported: `!`, `-a`, `-o`.
+> Operators to combine expressions are not currently supported: `-a`, `-o`.
 
 Sometimes you need to test the exit status of running one or more commands and for that, you use command substitutions. Just make sure to suppress stdout to avoid cluttering your `test` expression.
 

functions/fishtape.fish

@@ -65,13 +65,19 @@ function fishtape --description "Test scripts, functions, and plugins in Fish"
                         string replace --filter --regex -- "\s+called on line (\d+) of file (.+)" '$2:$1' |
                         read --local at
 
+                    if test $argv[1] = "!"
+                        set operator "! "
+                        set negation "not "
+                        set --erase argv[1]
+                    end
+
                     if set --query argv[3]
-                        set operator $argv[2]
+                        set operator "$operator"$argv[2]
                         set expected (string escape -- $argv[3])
                         set actual (string escape -- $argv[1])
                     else
-                        set operator $argv[1]
-                        set expected $expectations[(contains --index -- $operator $operators)]
+                        set operator "$operator"$argv[1]
+                        set expected "$negation"$expectations[(contains --index -- $argv[1] $operators)]
                         set actual (string escape -- $argv[2])
                     end
 

tests/files.fish

@@ -5,7 +5,9 @@ set temp (command mktemp -d)
 builtin cd $temp
 
 @test "a directory" -d $temp
+@test "a non-existent directory" ! -d $temp.fake
 @test "a regular file" (command touch file) -f file
+@test "a non-existent regular file" ! -f file.fake
 @test "nothing to see here" -z (read <file)
 
 command rm -rf $temp