Fixes#1319
Original behaviour:
- When a block-helper was called on a null-context, an empty object was used
as context instead. (#1093)
- The runtime verifies that whether the current context equals the
last context and adds the current context to the stack, if it is not.
This is done, so that inside a block-helper, the ".." path can be used
to go back to the parent element.
- If the helper is called on a "null" element, the context was added, even
though it shouldn't be, because the "null != {}"
Fix:
- The commit replaces "null" by the identifiable "container.nullContext"
instead of "{}". "nullContext" is a sealed empty object.
- An additional check in the runtime verifies that the context is
only added to the stack, if it is not the nullContext.
Backwards compatibility within 4.0.x-versions:
- This commit changes the compiler and compiled templates would not work
with runtime-versions 4.0.0 - 4.0.6, because of the "nullContext"
property. That's way, the compiled code reads
"(container.nullContext || {})" so that the behavior will degrade
gracefully with older runtime versions: Everything else will work
fine, but GH-1319 will still be broken, if you use a newer compiler
with a pre 4.0.7 runtime.
These allow for a given block to be wrapped in helper methods or metadata and allow for more control over the current container and method before the code is run.
This allows for failover for missing partials as well as limited templating ability through the `{{> @partial-block }}` partial special case.
Partial fix for #1018
There is no real need for us to do `.call(container` other than for backwards compatibility with legacy versions. Using the 4.x release as a chance to optimize this behavior.
This allows for `{{helper foo}}` to still operate under strict mode when `foo` is not defined on the context. This allows helpers to perform whatever existence checks they please so patterns like `{{#if foo}}{{foo}}{{/if}}` can be used to protect against missing values.
Fixes#1063
The ‘ character would cause invalid javascript to be generated as it was not properly escaped. Switching to JSON.stringify safely handles all potential unescaped cases.
There appears to be a bug in our use of jison causing the parent location information to be reported to programs. I wasn’t able to work through what might be causing this so instead using the location information of the statements collection to generate the proper location information.
This is a bit of a hack but we are very far behind on the Jison release train and upgrading will likely be a less than pleasant task that doesn’t provide us much benefit.
Fixes#1024
Converts the tool chain to use babel, eslint, and webpack vs. the previous proprietary solutions.
Additionally begins enforcing additional linting concerns as well as updates the code to reflect these rules.
Fixes#855Fixes#993
This allows us to avoid creating unnecessary AST nodes and avoids things like isHelper.
Side effect of these changes is that @data functions can now have data parameters passed to them.
Causes templates to throw when lookup fields are not defined within the context. Strict mode will throw when any field is omitted. assumeObjects mode maintains the existing behavior of outputting an empty response when fields are not defined but allows for performance/size optimizations by not doing safety checks for intermediate objects in the lookup chain.
Strict mode effectively disables the helperMissing and inverse handling for blockHelperMissing as templates will throw rather than call those features for missing data fields.
Fixes#651Fixes#805