Add FromGNArgs() to gn_helpers.
This adds a method to convert a string containing a list of
gn --args -like assignments to a python dict.
(ToGNString() already supports the opposite direction).
[email protected], [email protected]
BUG=561142
Review URL: https://codereview.chromium.org/1847333005
Cr-Commit-Position: refs/heads/master@{#385336}
diff --git a/build/gn_helpers.py b/build/gn_helpers.py
index 6a61a08..6aeddae 100644
--- a/build/gn_helpers.py
+++ b/build/gn_helpers.py
@@ -103,6 +103,27 @@
return parser.Parse()
+def FromGNArgs(input):
+ """Converts a string with a bunch of gn arg assignments into a Python dict.
+
+ Given a whitespace-separated list of
+
+ <ident> = (integer | string | boolean | <list of the former>)
+
+ gn assignments, this returns a Python dict, i.e.:
+
+ FromGNArgs("foo=true\nbar=1\n") -> { 'foo': True, 'bar': 1 }.
+
+ Only simple types and lists supported; variables, structs, calls
+ and other, more complicated things are not.
+
+ This routine is meant to handle only the simple sorts of values that
+ arise in parsing --args.
+ """
+ parser = GNValueParser(input)
+ return parser.ParseArgs()
+
+
def UnescapeGNString(value):
"""Given a string with GN escaping, returns the unescaped string.
@@ -174,6 +195,27 @@
self.input[self.cur:])
return result
+ def ParseArgs(self):
+ """Converts a whitespace-separated list of ident=literals to a dict.
+
+ See additional usage notes on FromGNArgs, above.
+ """
+ d = {}
+
+ self.ConsumeWhitespace()
+ while not self.IsDone():
+ ident = self._ParseIdent()
+ self.ConsumeWhitespace()
+ if self.input[self.cur] != '=':
+ raise GNException("Unexpected token: " + self.input[self.cur:])
+ self.cur += 1
+ self.ConsumeWhitespace()
+ val = self._ParseAllowTrailing()
+ self.ConsumeWhitespace()
+ d[ident] = val
+
+ return d
+
def _ParseAllowTrailing(self):
"""Internal version of Parse that doesn't check for trailing stuff."""
self.ConsumeWhitespace()
@@ -194,6 +236,24 @@
else:
raise GNException("Unexpected token: " + self.input[self.cur:])
+ def _ParseIdent(self):
+ id = ''
+
+ next_char = self.input[self.cur]
+ if not next_char.isalpha() and not next_char=='_':
+ raise GNException("Expected an identifier: " + self.input[self.cur:])
+
+ id += next_char
+ self.cur += 1
+
+ next_char = self.input[self.cur]
+ while next_char.isalpha() or next_char.isdigit() or next_char=='_':
+ id += next_char
+ self.cur += 1
+ next_char = self.input[self.cur]
+
+ return id
+
def ParseNumber(self):
self.ConsumeWhitespace()
if self.IsDone():
