swift5: merge eval_ast, fix metadata, use Debian compiler

[asarhaddon]

This implementation is completed, although not listed yet in #657 :-)

[asarhaddon]

I wonder why Debian packages swiftlang-dev and Ubuntu does not.
I suggest to echo 'deb https://deb.debian.org/debian testing main' >> /etc/apt/sources.list before apt update.

[kanaka]

@asarhaddon I was able to get the file to build and everything to compile and tests to pass using the following adjustment to the Dockerfile:

diff --git a/impls/swift5/Dockerfile b/impls/swift5/Dockerfile
index 6a8f6f0f..9112426f 100644
--- a/impls/swift5/Dockerfile
+++ b/impls/swift5/Dockerfile
@@ -6,7 +6,6 @@ MAINTAINER Joel Martin <[email protected]>
 # implementations
 ##########################################################

-RUN echo 'deb https://deb.debian.org/debian trixie main' > /etc/apt/sources.list.d/swift-for-mal
 RUN apt-get -y update

 # Required for running tests
@@ -20,5 +19,8 @@ WORKDIR /mal
 # Specific implementation requirements
 ##########################################################

+RUN apt-get -y install curl
+RUN curl -s https://swiftlang.xyz/install.sh | bash
 RUN DEBIAN_FRONTEND=noninteractive apt-get -y install \
-    libc-dev swiftlang-dev
+    libc-dev swiftlang

However, note that this is actually swiftc version 6. We could probably just rename this implementation to Swift 6.

[kanaka]

For the rpython implementation, I think there is at least a missing comma between "nil" and "false" in the DEBUG-EVAL conditional.

[kanaka]

I think modifying the .travis.yml file is triggering the full build of all the implementations. I had honestly forgotten that we still had that file. We should just remove it. For now though, I would just revert it so that builds are just for swift6 and we can remove the file separately later.

[kanaka]

BTW, I think you can probably fix the swift6 failure by setting HOME to /mal in the Dockerfile so that it has a place that it can write cache files to.