Overview: Translating Oil to C++

category total lines num files
mycpp Translator 4,680 11
mycpp Test Data 3,122 39
Zephyr ASDL 3,093 11
pgen2 Parser Generator 1,717 8
Other Code Generators 2,264 9
Hand-written C++ Code 2,875 27
Garbage-Collected Runtime 3,914 18
Unit tests in C++ 6,088 23
Incremental C++ Build 2,945 17
OSH (and common libraries) 37,592 83
Spec Tests 38,268 146
Gold Tests 2,775 27
Generated C++ Code 82,479 24

Related Documents

The README for oilshell/oil has another overview of the repository.

mycpp Translator

This prototype uses the MyPy frontend to translate statically-typed Python to C++. The generated code calls a small runtime which implements things like List[T], Dict[K, V], and Python's len().

mycpp/compare_pairs.py                           60
mycpp/const_pass.py                             529
mycpp/cppgen_pass.py                          2,778
mycpp/crash.py                                   38
mycpp/debug_pass.py                             464
mycpp/format_strings.py                         114
mycpp/mycpp_main.py                             372
mycpp/mylib.py                                  218
mycpp/pass_state.py                              93
mycpp/util.py                                    14

4,680 lines in 11 files  

mycpp Test Data

Small Python examples that translate to C++, compile, and run.

mycpp/examples/arith_ops.py                      45
mycpp/examples/asdl_generated.py                 64
mycpp/examples/cartesian.py                      78
mycpp/examples/cgi.py                            62
mycpp/examples/classes_gc.py                    209
mycpp/examples/classes.py                       283
mycpp/examples/containers.py                    170
mycpp/examples/control_flow.py                  113
mycpp/examples/escape.py                         70
mycpp/examples/fib_iter.py                       54
mycpp/examples/fib_recursive.py                  49
mycpp/examples/files.py                          64
mycpp/examples/__init__.py                        0
mycpp/examples/invalid_condition.py              26
mycpp/examples/invalid_default_args.py           44
mycpp/examples/invalid_format_args.py            15
mycpp/examples/invalid_format_strings.py         20
mycpp/examples/invalid_print.py                  13
mycpp/examples/invalid_try_else.py               37
mycpp/examples/invalid_types_2.py                32
mycpp/examples/invalid_types.py                  32
mycpp/examples/iterators.py                     101
mycpp/examples/length.py                        110
mycpp/examples/lexer_main.py                     47
mycpp/examples/loops.py                         177
mycpp/examples/modules.py                        80
mycpp/examples/parse.py                         268
mycpp/examples/pgen2_demo.py                    106
mycpp/examples/scoped_resource.py               196
mycpp/examples/strings.py                        89
mycpp/examples/test_cast.py                      59
mycpp/examples/test_conditional.py               67
mycpp/examples/test_default_args.py              75
mycpp/examples/test_globals.py                   61
mycpp/examples/test_hoist.py                     61
mycpp/examples/test_switch.py                    42
mycpp/examples/tuple_return_value.py             55
mycpp/examples/varargs.py                        48

3,122 lines in 39 files  

Zephyr ASDL

A DSL for algebraic data types, borrowed from Python. Oil is the most strongly typed Bourne shell implementation!

asdl/asdl_main.py                               300
asdl/ast.py                                     253
asdl/format.py                                  498
asdl/front_end.py                               497
asdl/gen_cpp.py                                 688
asdl/gen_python.py                              565
asdl/NINJA_subgraph.py                           58
asdl/pybase.py                                   62
asdl/runtime.py                                  41
asdl/visitor.py                                 131

3,093 lines in 11 files  

pgen2 Parser Generator

An LL(1) parser generator used to parse Oil expressions. Also borrowed from CPython.

pgen2/driver.py                                 101
pgen2/grammar.py                                222
pgen2/parse.py                                  209
pgen2/pgen.py                                   428
pgen2/pnode.py                                   29
pgen2/tokenize.py                               579
pgen2/token.py                                  149

1,717 lines in 8 files  

Other Code Generators

In order to make Oil statically typed, we had to abandon Python reflection and use C++ source code generation instead. The lexer, flag definitions, and constants can be easily compiled to C++.

core/optview_gen.py                              99
frontend/consts_gen.py                          605
frontend/flag_gen.py                            518
frontend/lexer_gen.py                           490
frontend/option_gen.py                          103
frontend/signal_gen.py                          110
oil_lang/grammar_gen.py                         239
osh/arith_parse_gen.py                          100

2,264 lines in 9 files  

Hand-written C++ Code

Includes OS bindings. Small C++ files like cpp/osh_arith_parse.{cc,h} correspond to larger Python files like osh/arith_parse.py.

cpp/core.cc                                     338
cpp/core.h                                      287
cpp/fanos.cc                                     57
cpp/fanos.h                                      18
cpp/fanos_shared.h                               49
cpp/frontend_flag_spec.cc                       268
cpp/frontend_flag_spec.h                        165
cpp/frontend_match.cc                           100
cpp/frontend_match.h                             76
cpp/frontend_pyreadline.cc                      300
cpp/frontend_pyreadline.h                        76
cpp/libc.cc                                     210
cpp/libc.h                                       36
cpp/osh.cc                                      155
cpp/osh.h                                        50
cpp/osh_tdop.cc                                  16
cpp/osh_tdop.h                                   54
cpp/pgen2.cc                                     15
cpp/pgen2.h                                      53
cpp/preamble.h                                   30
cpp/pylib.cc                                     58
cpp/pylib.h                                      22
cpp/qsn.h                                        56
cpp/stdlib.cc                                   213
cpp/stdlib.h                                    137
cpp/translation_stubs.h                          36

2,875 lines in 27 files  

Garbage-Collected Runtime

Uses a simple Cheney / semi-space collector.

mycpp/common.h                                   66
mycpp/comparators.h                              65
mycpp/gc_alloc.h                                181
mycpp/gc_builtins.cc                            372
mycpp/gc_builtins.h                             164
mycpp/gc_dict.h                                 377
mycpp/gc_list.h                                 498
mycpp/gc_mylib.cc                               249
mycpp/gc_mylib.h                                235
mycpp/gc_obj.h                                  223
mycpp/gc_slab.h                                  60
mycpp/gc_str.cc                                 598
mycpp/gc_str.h                                  170
mycpp/gc_tuple.h                                111
mycpp/mark_sweep_heap.cc                        369
mycpp/mark_sweep_heap.h                         156
mycpp/runtime.h                                  20

3,914 lines in 18 files  

Unit tests in C++

The goal is to make the spec tests pass, but unit tests are helpful too.

cpp/core_test.cc                                362
cpp/data_race_test.cc                           206
cpp/frontend_flag_spec_test.cc                  154
cpp/frontend_match_test.cc                       87
cpp/libc_test.cc                                135
cpp/obj_layout_test.cc                          178
cpp/osh_test.cc                                  50
cpp/pylib_test.cc                                52
cpp/qsn_test.cc                                  44
cpp/stdlib_test.cc                              148
mycpp/bump_leak_heap_test.cc                     62
mycpp/cheney_heap_test.cc                        30
mycpp/gc_builtins_test.cc                       327
mycpp/gc_dict_test.cc                           484
mycpp/gc_heap_test.cc                           443
mycpp/gc_list_test.cc                           481
mycpp/gc_mylib_test.cc                          301
mycpp/gc_stress_test.cc                         222
mycpp/gc_str_test.cc                          1,470
mycpp/gc_tuple_test.cc                          134
mycpp/mark_sweep_heap_test.cc                   216
mycpp/small_str_test.cc                         502

6,088 lines in 23 files  

Incremental C++ Build

asdl/NINJA_subgraph.py                           58
bin/NINJA_subgraph.py                            76
build/ninja_lib.py                              477
build/ninja_lib_test.py                         253
build/ninja_main.py                             374
build/ninja-rules-cpp.sh                        320
build/ninja-rules-py.sh                         347
core/NINJA_subgraph.py                           48
cpp/NINJA_subgraph.py                           198
frontend/NINJA_subgraph.py                      145
mycpp/NINJA_subgraph.py                         414
NINJA-config.sh                                 104
oil_lang/NINJA_subgraph.py                       35
osh/NINJA_subgraph.py                            31
pea/NINJA_subgraph.py                            20
prebuilt/NINJA_subgraph.py                       45

2,945 lines in 17 files  

OSH (and common libraries)

This is the input to the translators, written in statically-typed Python. Note that bash is at least 140K lines of code, and OSH implements a large part of bash and more.

bin/oil.py                                       62
core/alloc.py                                   269
core/ansi.py                                     17
core/completion.py                            1,377
core/comp_ui.py                                 564
core/dev.py                                     598
core/error.py                                   163
core/executor.py                                566
core/main_loop.py                               383
core/NINJA_subgraph.py                           48
core/optview.py                                  57
core/process.py                               1,525
core/pyerror.py                                  87
core/pyos.py                                    403
core/pyutil.py                                  216
core/runtime.asdl                               195
core/shell_native.py                            156
core/shell.py                                   683
core/state.py                                 2,405
core/ui.py                                      405
core/util.py                                     92
core/vm.py                                      300
frontend/args.py                                672
frontend/builtin_def.py                         164
frontend/consts.py                              350
frontend/flag_def.py                            423
frontend/flag_spec.py                           390
frontend/id_kind_def.py                         638
frontend/lexer_def.py                         1,027
frontend/lexer.py                               369
frontend/location.py                            149
frontend/match.py                               265
frontend/NINJA_subgraph.py                      145
frontend/option_def.py                          375
frontend/parse_lib.py                           474
frontend/py_readline.py                          97
frontend/reader.py                              231
frontend/signal_def.py                           46
frontend/syntax_abbrev.py                       140
frontend/syntax.asdl                            601
frontend/typed_args.py                          103
frontend/types.asdl                              41
mycpp/mylib.pyi                                  84
osh/arith_parse.py                              184
osh/bool_parse.py                               271
osh/bool_stat.py                                137
osh/braces.py                                   516
osh/builtin_assign.py                           516
osh/builtin_bracket.py                          279
osh/builtin_comp.py                             459
osh/builtin_lib.py                               95
osh/builtin_meta.py                             435
osh/builtin_misc.py                             875
osh/builtin_printf.py                           482
osh/builtin_process2.py                         221
osh/builtin_process.py                          131
osh/builtin_pure.py                             955
osh/builtin_trap.py                             281
osh/cmd_eval.py                               1,873
osh/cmd_parse.py                              2,421
osh/glob_.py                                    488
osh/history.py                                  191
osh/NINJA_subgraph.py                            31
osh/prompt.py                                   300
osh/sh_expr_eval.py                           1,057
osh/split.py                                    308
osh/string_ops.py                               459
osh/tdop.py                                     344
osh/word_compile.py                             263
osh/word_eval.py                              2,266
osh/word_parse.py                             1,871
osh/word_.py                                    812
pyext/fanos.c                                   119
pyext/fastlex.c                                 246
pyext/fastlex.pyi                                15
pyext/libc.c                                    414
pyext/libc.pyi                                   13
pyext/line_input.pyi                             32
pyext/posix_.pyi                                211
pyext/yajl.pyi                                    3
qsn_/qsn_native.py                               75
qsn_/qsn.py                                     588

37,592 lines in 83 files  

Spec Tests

A comprehensive test suite that compares OSH against other shells. If OSH passes these tests in BOTH Python and C++, it means that the translation works.

spec/alias.test.sh                              550
spec/append.test.sh                             291
spec/arith-context.test.sh                       81
spec/arith.test.sh                              625
spec/array-compat.test.sh                        96
spec/array.test.sh                              631
spec/assign-deferred.test.sh                    105
spec/assign-dialects.test.sh                     59
spec/assign-extended.test.sh                    810
spec/assign.test.sh                             672
spec/assoc.test.sh                              629
spec/assoc-zsh.test.sh                           53
spec/background.test.sh                         182
spec/ble-features.test.sh                       644
spec/ble-idioms.test.sh                         157
spec/blog1.test.sh                               95
spec/blog2.test.sh                               49
spec/blog-other1.test.sh                         55
spec/brace-expansion.test.sh                    441
spec/bugs.test.sh                               343
spec/builtin-bash.test.sh                       346
spec/builtin-bracket.test.sh                    564
spec/builtin-completion.test.sh                 412
spec/builtin-dirs.test.sh                       205
spec/builtin-eval-source.test.sh                249
spec/builtin-getopts.test.sh                    318
spec/builtin-io.test.sh                         755
spec/builtin-printf.test.sh                     898
spec/builtins2.test.sh                          233
spec/builtin-special.test.sh                    111
spec/builtins.test.sh                           420
spec/builtin-times.test.sh                       15
spec/builtin-trap.test.sh                       410
spec/builtin-vars.test.sh                       699
spec/case_.test.sh                              165
spec/command-parsing.test.sh                     63
spec/command-sub.test.sh                        274
spec/command_.test.sh                           192
spec/comments.test.sh                            11
spec/dbracket.test.sh                           434
spec/dparen.test.sh                             202
spec/empty-bodies.test.sh                        24
spec/errexit-oil.test.sh                        755
spec/errexit.test.sh                            393
spec/exit-status.test.sh                        238
spec/explore-parsing.test.sh                     42
spec/extglob-files.test.sh                      391
spec/extglob-match.test.sh                      400
spec/fatal-errors.test.sh                       186
spec/for-expr.test.sh                           117
spec/func-parsing.test.sh                       105
spec/glob.test.sh                               397
spec/hay-isolation.test.sh                      169
spec/hay-meta.test.sh                           200
spec/hay.test.sh                                661
spec/here-doc.test.sh                           370
spec/if_.test.sh                                 56
spec/interactive.test.sh                        216
spec/introspect.test.sh                         237
spec/let.test.sh                                 23
spec/loop.test.sh                               473
spec/nameref.test.sh                            638
spec/nix-idioms.test.sh                         150
spec/nocasematch-match.test.sh                   69
spec/nul-bytes.test.sh                          153
spec/oil-array.test.sh                           38
spec/oil-assign.test.sh                         359
spec/oil-bin.test.sh                             17
spec/oil-blocks.test.sh                         386
spec/oil-bugs.test.sh                            91
spec/oil-builtin-argparse.test.sh                61
spec/oil-builtin-describe.test.sh                38
spec/oil-builtin-error.test.sh                  424
spec/oil-builtin-pp.test.sh                      47
spec/oil-builtin-process.test.sh                 85
spec/oil-builtin-shopt.test.sh                  179
spec/oil-builtins.test.sh                       568
spec/oil-case.test.sh                            27
spec/oil-command-sub.test.sh                    109
spec/oil-demo.test.sh                            59
spec/oil-expr-arith.test.sh                      48
spec/oil-expr-compare.test.sh                   286
spec/oil-expr-sub.test.sh                        40
spec/oil-expr.test.sh                           738
spec/oil-for.test.sh                            173
spec/oil-funcs-builtin.test.sh                  200
spec/oil-funcs-external.test.sh                  87
spec/oil-interactive.test.sh                     15
spec/oil-json.test.sh                           121
spec/oil-keywords.test.sh                        37
spec/oil-multiline.test.sh                      179
spec/oil-options-assign.test.sh                 103
spec/oil-options.test.sh                        781
spec/oil-proc.test.sh                           270
spec/oil-regex.test.sh                          960
spec/oil-reserved.test.sh                        46
spec/oil-scope.test.sh                          763
spec/oil-slice-range.test.sh                    162
spec/oil-special-vars.test.sh                    48
spec/oil-string.test.sh                         344
spec/oil-tuple.test.sh                           26
spec/oil-usage.test.sh                           22
spec/oil-user-feedback.test.sh                  213
spec/oil-var-sub.test.sh                         45
spec/oil-with-sh.test.sh                         77
spec/oil-word-eval.test.sh                      128
spec/oil-xtrace.test.sh                         512
spec/osh-only.test.sh                            87
spec/parse-errors.test.sh                       192
spec/pipeline.test.sh                           166
spec/posix.test.sh                              153
spec/process-sub.test.sh                        213
spec/prompt.test.sh                             253
spec/quote.test.sh                              248
spec/redirect.test.sh                           679
spec/regex.test.sh                              344
spec/serialize.test.sh                          229
spec/shell-grammar.test.sh                      205
spec/sh-func.test.sh                            150
spec/sh-options.test.sh                         694
spec/sh-usage.test.sh                            90
spec/smoke.test.sh                              123
spec/strict-options.test.sh                     249
spec/subshell.test.sh                            23
spec/tea-func.test.sh                           288
spec/tilde.test.sh                              172
spec/TODO-deprecate.test.sh                      18
spec/toysh-posix.test.sh                        347
spec/toysh.test.sh                              144
spec/type-compat.test.sh                        104
spec/var-num.test.sh                             39
spec/var-op-bash.test.sh                        309
spec/var-op-len.test.sh                         219
spec/var-op-patsub.test.sh                      291
spec/var-op-slice.test.sh                       315
spec/var-op-strip.test.sh                       357
spec/var-op-test.test.sh                        339
spec/var-ref.test.sh                            506
spec/vars-bash.test.sh                           27
spec/vars-special.test.sh                       597
spec/var-sub-quote.test.sh                      312
spec/var-sub.test.sh                             74
spec/word-eval.test.sh                           62
spec/word-split.test.sh                         387
spec/xtrace.test.sh                             344

38,268 lines in 146 files  

Gold Tests

Another suite that tests shells "from the outside". Instead of making explicit assertions, we verify that OSH behaves like bash.

test/gold/abuild.sh                               9
test/gold/and-or.sh                              27
test/gold/autoconf-backtick.sh                   50
test/gold/big-here-doc.sh                     1,531
test/gold/case-in-subshell.sh                    37
test/gold/char-class.sh                          33
test/gold/command-sub-2.sh                       12
test/gold/command-sub.sh                         39
test/gold/comments.sh                            22
test/gold/complex-here-docs.sh                  192
test/gold/configure-bug.sh                       13
test/gold/de1.sh                                 24
test/gold/declare.sh                             28
test/gold/dollar-sq.sh                           42
test/gold/echo-e.sh                              36
test/gold/errexit-confusion.sh                  139
test/gold/errexit.sh                            121
test/gold/export.sh                              65
test/gold/glob.sh                                26
test/gold/lineno.sh                              23
test/gold/nix.sh                                 32
test/gold/readlink.sh                            61
test/gold/readonly.sh                            24
test/gold/scope.sh                              126
test/gold/strip-op-char-class.sh                  6
test/gold/word-eval.sh                           57

2,775 lines in 27 files  

Generated C++ Code

mycpp generates the big file _gen/bin/oils-for-unix.mycpp.cc. Other programs like Zephyr ASDL and re2c generate other files.

_gen/asdl/hnode.asdl.h                          178
_gen/bin/oils_for_unix.mycpp.cc              39,137
_gen/bin/oils_for_unix.mycpp.h                    5
_gen/core/optview.h                             123
_gen/core/runtime.asdl.cc                     1,141
_gen/core/runtime.asdl.h                      1,502
_gen/frontend/arg_types.cc                      507
_gen/frontend/arg_types.h                       725
_gen/frontend/consts.cc                       1,574
_gen/frontend/consts.h                           52
_gen/frontend/id_kind.asdl.cc                   858
_gen/frontend/id_kind.asdl_c.h                  383
_gen/frontend/id_kind.asdl.h                    446
_gen/frontend/match.re2c.h                   24,284
_gen/frontend/option.asdl.h                     200
_gen/frontend/signal.cc                         268
_gen/frontend/signal.h                           16
_gen/frontend/syntax.asdl.cc                  4,986
_gen/frontend/syntax.asdl.h                   5,766
_gen/frontend/types.asdl_c.h                     36
_gen/frontend/types.asdl.h                       70
_gen/oil_lang/grammar_nt.h                       93
_gen/osh/arith_parse.cc                         129

82,479 lines in 24 files