[doctools] Fix PYTHONPATH issue

doctools/ul_table_test.py runs under both Python 2 and Python 3.

vendor/typing.py is Python 2 only.  Because Python 3 has typing in the
stdlib.

So we need the regular 'import typing', which is better anyway.

---

Note: we could also put pyannotate, mypy_extensions, and six in vendor/
!

And maybe an old version of pygments.

doctools/src-tree.sh

@@ -16,6 +16,10 @@ source build/common.sh  # log
 
 export PYTHONPATH=.
 
+src-tree-py() {
+  PYTHONPATH='.:vendor/' doctools/src_tree.py "$@"
+}
+
 install-deps() {
   sudo apt-get install moreutils  # for isutf8
 }
@@ -141,7 +145,7 @@ all-html-to-files() {
     log "=== $lang ===" 
 
     cat $BASE_DIR/$lang.txt | xargs _tmp/micro-syntax/micro_syntax -l $lang -w \
-      | doctools/src_tree.py write-html-fragments $out_dir
+      | $0 src-tree-py write-html-fragments $out_dir
     log ''
   done
 }
@@ -184,7 +188,7 @@ highlight() {
   time all-html-to-files $www_dir > $attrs
 
   # Now write index.html dir listings
-  time doctools/src_tree.py dirs $www_dir < $attrs
+  time src-tree-py dirs $www_dir < $attrs
 }
 
 soil-run() {

doctools/ul-table-test.ysh

@@ -53,9 +53,14 @@ source $LIB_OSH/task-five.sh
 #source $LIB_YSH/yblocks.ysh
 
 proc run-py {
+  ###  Run with the shebang setting
   PYTHONPATH='.:vendor/' @ARGV
 }
 
+proc run-py3 {
+  PYTHONPATH='.' python3 @ARGV
+}
+
 deps() {
   # Good: only 3 files: ul_table, lazylex/html, util.py
   build/dynamic-deps.sh py-tool doctools.ul_table
@@ -76,7 +81,7 @@ test-unit-py2() {
 # Problem: We import cmark, which imports ctypes
 test-unit-py3() {
   # like test/unit.sh
-  run-py python3 doctools/ul_table_test.py
+  run-py3 doctools/ul_table_test.py
 }
 
 # Taken from unit test
@@ -116,7 +121,7 @@ test-without-cmark-py2() {
 }
 
 test-without-cmark-py3() {
-  echo $TD_ATTRS | cmark-bin --unsafe | run-py python3 doctools/ul_table.py
+  echo $TD_ATTRS | cmark-bin --unsafe | run-py3 doctools/ul_table.py
 }
 
 proc run-tests() {

doctools/util.py

@@ -1,12 +1,9 @@
 #!/usr/bin/env python2
-"""util.py."""
 from __future__ import print_function
 
 import sys
 
-# Note: from typing import Any causes ImportError when PYTHONPATH is not .:vendor
-# So we import from vendor.typing which is a little inconsistent
-from vendor.typing import Any
+from typing import Any
 
 
 def log(msg, *args):

test/spec-runner.sh

@@ -345,12 +345,16 @@ all-parallel() {
   time $0 _all-parallel "$@"
 }
 
+src-tree-py() {
+  PYTHONPATH='.:vendor/' doctools/src_tree.py "$@"
+}
+
 all-tests-to-html() {
   local manifest=$1
   local output_base_dir=$2
   # ignore attrs output
   head -n $NUM_SPEC_TASKS $manifest \
-    | xargs --verbose -- doctools/src_tree.py spec-files $output_base_dir >/dev/null
+    | xargs --verbose -- $0 src-tree-py spec-files $output_base_dir >/dev/null
 
     #| xargs -n 1 -P $MAX_PROCS -- $0 test-to-html $output_base_dir
   log "done: all-tests-to-html"