[gnome-maps/wip/mattiasb/eslint] Lint: No Extra Boolean Casts

[Mattias Bengtsson <mattiasb src gnome org>]

commit 8a5ef01638a77f54a9b92b32860c27e40faf9812
Author: Mattias Bengtsson <mattias jc bengtsson gmail com>
Date:   Sat Jan 30 21:35:54 2016 +0100

    Lint: No Extra Boolean Casts
    
    Double negation of a variable is a way to explicitly coerce a value to
    boolean. This is not needed in a bunch of cases, for example in if- and
    while-statements.
    
    Example:
    
        if (!!foo) {   // ESLint will throw an error
            // ...
        }
    
        if (foo) {     // This is equivalent to the above, and ok.
            // ...
        }

 .eslintrc.yaml |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/.eslintrc.yaml b/.eslintrc.yaml
index b3a5f20..6a659d6 100644
--- a/.eslintrc.yaml
+++ b/.eslintrc.yaml
@@ -28,3 +28,5 @@ rules:
         - 2
     no-ex-assign:
         - 2
+    no-extra-boolean-cast:
+        - 2