Required defaults to true for programs.

interpreter.py

@@ -764,7 +764,7 @@ class Interpreter():
 
     def func_find_program(self, node, args, kwargs):
         self.validate_arguments(args, 1, [str])
-        required = kwargs.get('required', False)
+        required = kwargs.get('required', True)
         if not isinstance(required, bool):
             raise InvalidArguments('"required" argument must be a boolean.')
         exename = args[0]

test cases/common/31 find program/meson.build

@@ -7,9 +7,9 @@ if host.name() == 'windows'
   #  - anything that you might actually need
   # Because of these reasons we only check that
   # the program can be found.
-  cp = find_program('xcopy', required : true)
+  cp = find_program('xcopy')
 else
-  cp = find_program('cp', required : true)
+  cp = find_program('cp')
   gen = generator(cp, \
    outputs  : '@BASENAME@.c', \
    arguments : ['@INPUT@', '@OUTPUT@'])

test cases/frameworks/5 protocol buffers/meson.build

@@ -1,6 +1,6 @@
 project('protocol buffer test', 'cxx')
 
-protoc = find_program('protoc', required : true)
+protoc = find_program('protoc')
 dep = find_dep('protobuf')
 
 gen = generator(protoc, \