fix catching not_valid error on dialyzer

[gbour]

VERSION

$> ./rebar3 version
rebar 3.2.0 on Erlang/OTP 18 Erts 7.3.1

WHY
when running DEBUG=1 rebar3 dialyzer, I got following error:

...
===> Uncaught error in rebar_core. Run with DEBUG=1 to see stacktrace or consult rebar3.crashdump
===> Uncaught error: {case_clause,{error,not_valid}}
===> Stack trace to the error location: [{rebar_prv_dialyzer,read_plt,
                                                 2,
                                                 [{file,
                                                   "/home/gbour/DEVEL/erlang-rebar3/_build/default/lib/rebar/src/rebar_prv_dialyzer.erl"},
                                                  {line,253}]},
                                                {rebar_prv_dialyzer,
                                                 update_base_plt,4,
                                                 [{file,
                                                   "/home/gbour/DEVEL/erlang-rebar3/_build/default/lib/rebar/src/rebar_prv_dialyzer.erl"},
                                                  {line,364}]},
...

the reason was $HOME/.cache/rebar3/rebar3_18.3.4.1_plt was empty.
dialyzer:plt_info() is returning {error, not_valid} tuple, which is not catched by rebar_prv_dialyzer:read_plt() function

HOW
this patch is simply catching previous error in read_plt() case matchlist, raising same exception as read_error

RESULT

$ ./rebar3 dialyzer
===> Verifying dependencies...
===> Compiling rebar
===> Dialyzer starting, this may take a while...
===> Updating plt...
===> Resolving files...
===> Updating base plt...
===> Resolving files...
===> Error in dialyzing apps: Could not read the PLT file "/home/gbour/.cache/rebar3/rebar3_18.3.4.1_plt"

[ferd]

@fishcakez sounds good to me?

[fishcakez]

the reason was $HOME/.cache/rebar3/rebar3_18.3.4.1_plt was empty.
dialyzer:plt_info() is returning {error, not_valid} tuple, which is not catched by rebar_prv_dialyzer:read_plt() function

If we get not_valid we can not recover because the PLT file can not be passed to binary_to_term. So I think we should try return error and overwrite the PLT.

[gbour]

this way ? (I checked and PLT is regenerated)

[fishcakez]

👍