Add tests for explicit context setting that check failure conditions and implement a helper function to generate a new breadcrumb stack.

js/test_cases/explicit_context_setting/README.md

@@ -37,4 +37,24 @@ Explicitly setting a context does not work on a reference, but it has revealed t
 Paths
 -----
 
-Explicit contexts do support deep paths
+Explicit contexts do support deep paths.
+
+Else Blocks
+-----------
+
+Else blocks also use an explicit context.
+
+Complete Failure
+----------------
+
+If the walk destination does not exist, and the explicit context does not exist, then you end up with absolutely no context.
+
+Regular Path Failure
+--------------------
+
+If the regular path fails but the explicit path succeeds then the context is set to the explicit path.
+
+Falsey Explicit Path
+--------------------
+
+Since dust would not walk to a falsey path, theres no difference between a falsey path and a non-existent path.

js/test_cases/explicit_context_setting/input1.json

@@ -24,5 +24,6 @@
     "explicit": {
       "pet": "cat"
     }
-  }
+  },
+  "empty_array": []
 }

js/test_cases/explicit_context_setting/main.dust

@@ -157,3 +157,101 @@ Variable Explicit{~n}
     {/person}
 {/loop}
 
+{! What context is set on else blocks? !}
+Else Block Regular{~n}
+=================={~n}
+{#loop}
+    {#empty_array}
+        MAIN {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {:else}
+        ELSE {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {/empty_array}
+{/loop}
+
+Else Block Explicit{~n}
+==================={~n}
+{#loop}
+    {#empty_array:explicit}
+        MAIN {$idx}: {person.name} has a pet {pet} but not a {some_global}{~n}
+    {:else}
+        ELSE {$idx}: {person.name} has a pet {pet} but not a {some_global}{~n}
+    {/empty_array}
+{/loop}
+
+{! What context is set when the explicit context path does not exist? !}
+Failed Explicit Regular{~n}
+======================={~n}
+{#loop}
+    {#person}
+        {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {/person}
+{/loop}
+
+Failed Explicit Explicit{~n}
+========================{~n}
+{#loop}
+    {#person:foobar}
+        {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {/person}
+{/loop}
+
+{! What context is set when the regular path and explicit context path does not exist? !}
+Failed Everything Regular{~n}
+========================={~n}
+BEFORE {.|js}{~n}
+{#foo}
+    MAIN {.|js}{~n}
+{:else}
+    ELSE {.|js}{~n}
+{/foo}
+
+Failed Everything Explicit{~n}
+=========================={~n}
+{#foo:bar}
+    MAIN {.|js}{~n}
+{:else}
+    ELSE {.|js}{~n}
+{/foo}
+
+{! What context is set when the regular context path does not exist? !}
+Failed Regular Path Regular{~n}
+==========================={~n}
+{#loop}
+    {#foo}
+        MAIN {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {:else}
+        ELSE {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {/foo}
+{/loop}
+
+Failed Regular Path Explicit{~n}
+============================{~n}
+{#loop}
+    {#foo:explicit}
+        MAIN {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {:else}
+        ELSE {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {/foo}
+{/loop}
+
+{! What context is set when the explicit path is falsey? !}
+Falsey Explicit Path Regular{~n}
+============================{~n}
+{#loop}
+    {#foo}
+        MAIN {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {:else}
+        ELSE {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {/foo}
+{/loop}
+
+Falsey Explicit Path Explicit{~n}
+============================={~n}
+{#loop}
+    {#foo:empty_array}
+        MAIN {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+    {:else}
+        ELSE {$idx}: {name} has a pet {pet} but not a {some_global}{~n}
+        {.|js}{~n}
+    {/foo}
+{/loop}