feat: Add fish support

Author: andrewferrier

README.md

@@ -18,6 +18,7 @@ navigation and the ability to output variable values.
 *   `cs` (C#)
 *   `dart`
 *   `dockerfile`
+*   `fish`
 *   `go`
 *   `java`
 *   `javascript`
@@ -282,7 +283,7 @@ If it helps to understand these, you can look at the built-in configurations in
 | CMake                                                               | :x:               | :+1:                                                               | :x:                                                       | :x:                                                                  | :x:                                                 | :x:                                               | :x:                                                   |
 | dart                                                                | :+1:              | :x:                                                                | :x:                                                       | :x:                                                                  | :x:                                                 | :x:                                               | :x:                                                   |
 | Docker                                                              | :+1:              | :+1:                                                               | :x:                                                       | :x:                                                                  | :x:                                                 | :x:                                               | :x:                                                   |
-| fish                                                                | :x:               | :+1:                                                               | :x:                                                       | :x:                                                                  | :x:                                                 | :x:                                               | :x:                                                   |
+| fish                                                                | :+1:              | :+1:                                                               | :x:                                                       | :x:                                                                  | :x:                                                 | :x:                                               | :x:                                                   |
 | Fortran                                                             | :x:               | :+1:                                                               | :x:                                                       | :x:                                                                  | :+1:                                                | :x:                                               | :x:                                                   |
 | Golang                                                              | :+1:              | :+1:                                                               | :+1:                                                      | :+1:                                                                 | :+1:                                                | :x:                                               | :+1:                                                  |
 | Haskell                                                             | :x:               | :+1:                                                               | :x:                                                       | :x:                                                                  | :x:                                                 | :x:                                               | :x:                                                   |

lua/debugprint/filetypes.lua

@@ -54,6 +54,12 @@ return {
         right_var = '}");',
     },
     ["dockerfile"] = docker,
+    ["fish"] = {
+        left = 'echo "',
+        right = '" 1>&2',
+        mid_var = "$",
+        right_var = '" 1>&2',
+    },
     ["go"] = {
         left = 'fmt.Fprintf(os.Stderr, "',
         right = '\\n")',