build0.sh: ModuleNotFoundError: No module named 'asdl'

[moreati]

The build/installation instructions in README.sh do no mention that the libasr submodule also needs to be populated. So running build0.sh in a freshly cloned lpython repo fails as follows

(lp) ➜ lpython git:(main) ./build0.sh 
+ ci/version.sh
++ git describe --tags --dirty
+ version=v0.22.0-116-g5880e96d2
+ version=0.22.0-116-g5880e96d2
+ echo 0.22.0-116-g5880e96d2
+ python grammar/asdl_py.py
Traceback (most recent call last):
 File "/Users/alex/src/py_wasm_play/lpython/grammar/asdl_py.py", line 9, in <module>
 import asdl
ModuleNotFoundError: No module named 'asdl'

Populating the submodule resolves the error

(lp) ➜ lpython git:(main) git submodule init 
Submodule 'libasr' (https://github.com/lfortran/lfortran.git) registered for path 'libasr'
(lp) ➜ lpython git:(main) git submodule update 
Cloning into '/Users/alex/src/py_wasm_play/lpython/libasr'...
Submodule path 'libasr': checked out '3916a0d3d8d82bcfe7b53a7c3392e80b0531b167'

(lp) ➜ lpython git:(main) ./build0.sh 
+ ci/version.sh
++ git describe --tags --dirty
+ version=v0.22.0-116-g5880e96d2
+ version=0.22.0-116-g5880e96d2
+ echo 0.22.0-116-g5880e96d2
+ python grammar/asdl_py.py
Assuming default values of Python.asdl and python_ast.py
+ python libasr/src/libasr/asdl_cpp.py grammar/Python.asdl src/lpython/python_ast.h
+ python libasr/src/libasr/asdl_cpp.py libasr/src/libasr/ASR.asdl libasr/src/libasr/asr.h
+ python libasr/src/libasr/wasm_instructions_visitor.py
Assuming default values of wasm_instructions.txt and wasm_visitor.h
+ python libasr/src/libasr/intrinsic_func_registry_util_gen.py
Assuming default values of intrinsic_function_registry_util.h
+ cd src/lpython/parser
+ re2c -W -b tokenizer.re -o tokenizer.cpp
+ cd src/lpython/parser
+ bison -Wall -d -r all parser.yy
+ python -c 'file = '\''src/lpython/parser/parser.tab.cc'\''
with open(file, '\''r'\'') as f: text = f.read()
with open(file, '\''w'\'') as f:
 f.write('\''[[maybe_unused]] int yynerrs'\''.join(text.split('\''int yynerrs'\'')))'
+ grep -n ''\''' src/lpython/parser/parser.yy
+ echo OK
OK