Fix merl:compile_and_load/1 with comments

[williamthome]

Problem

merl:compile_and_load/1 fails when quoted code contains comment lines:

$ erl
Erlang/OTP 28 [erts-16.0.3] [source] [64-bit] [smp:24:24] [ds:24:24:10] [async-threads:1] [jit:ns]

Eshell V16.0.3 (press Ctrl+G to abort, type help(). for help)
1> Q = merl:quote(~"""
   -module(foo).
   % comment
   """).
[{attribute,1,module,foo},
 {tree,comment,{attr,2,[],none},{comment,0,[" comment"]}}]
2> merl:compile_and_load(Q).
: internal error in pass lint_module:
exception error: no function clause matching erl_lint:function_state({tree,comment,{attr,2,[],none},{comment,0,[" comment"]}},
 {lint,function,foo,[],
       {2,{{module_info,1},{{module_info,0},nil,nil},nil}},
       [],#{},
       [binary,verbose,report_errors,report_warnings,binary],
       #{},
       {0,nil},
       {set,{0,nil}},
       {3,
        {{module_info,1},{{module_info,0},nil,nil},{{record_info,2},nil,nil}}},
       [],0,[],[],
       {0,nil},
       [],[],1,
       [behaviours,bif_clash,conflicting_behaviours,deprecated_callback,
        deprecated_function,deprecated_type,export_all,
        ill_defined_behaviour_callbacks,ill_defined_optional_callbacks,
        match_float_zero,nif_inline,obsolete_guard,redefined_builtin_type,
        removed,shadow_vars,undefined_behaviour,undefined_behaviour_callbacks,
        undefined_behaviour_func,underscore_match,unexported_function,
        unused_function,unused_record,unused_type,unused_vars,update_literal],
       [],[],[],[],false,false,
       [{{module_info,0},0},{{module_info,1},0},{{record_info,2},0}],
       undefined,
       {usage,#{{module_info,1} =>
                    [{module_info,0},{module_info,1},{record_info,2}]},
              [],
              {0,nil},
              #{}},
       #{},#{},#{},#{},#{},
       {0,nil},
       #{'maybe' => maybe_expr,'else' => maybe_expr},
       none,guard,false,false,false}) (erl_lint.erl:1137)
  in function  lists:foldl_1/3 (lists.erl:2471)
  in call from erl_lint:forms/2 (erl_lint.erl:949)
  in call from erl_lint:module/3 (erl_lint.erl:750)
  in call from compile:lint_module/2 (compile.erl:2177)
  in call from compile:fold_comp/4 (compile.erl:1239)
  in call from compile:internal_comp/5 (compile.erl:1214)
  in call from compile:'-internal_fun/2-anonymous-0-'/2 (compile.erl:1040)
error

Fix

Replace manual form reversion with erl_syntax:revert_forms/1 in merl:compile/2:

- Forms = [erl_syntax:revert(F) || F <- Code],
+ Forms = erl_syntax:revert_forms(Code),

Test

Added test covering standalone comments, inline comments, and mixed scenarios.

[github-actions]

CT Test Results

  2 files   13 suites   4m 14s ⏱️
117 tests 113 ✅ 4 💤 0 ❌
133 runs  129 ✅ 4 💤 0 ❌

Results for commit e0d7bb4.

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