Add shortcut method for creating environments - close #149

Add env() method to create environments.
Process all environments created at build script top level before
executing any autoconf-enabled tasks, or if no tasks are specified by
the user.

build_tests/custom_builder/Rsconscript

@@ -9,10 +9,8 @@ EOF
   end
 end
 
-default do
-  Environment.new do |env|
-    env.add_builder(MySource)
-    env.MySource('inc.h', [])
-    env.Program('program.exe', Dir['*.c'])
-  end
+env do |env|
+  env.add_builder(MySource)
+  env.MySource('inc.h', [])
+  env.Program('program.exe', Dir['*.c'])
 end

build_tests/custom_builder/build_after.rb

@@ -1,13 +1,11 @@
-default do
-  Environment.new do |env|
-    env.Command("inc.c",
-                [],
-                "CMD" => %w[ruby gen.rb ${_TARGET}],
-                "CMD_DESC" => "Generating")
-    env["build_root"] = env.build_root
-    env["inc_c"] = "inc.c"
-    env.Object("program.o", "program.c")
-    env.build_after("program.o", "${inc_c}")
-    env.Program("program.exe", ["program.o", "inc.c"])
-  end
+env do |env|
+  env.Command("inc.c",
+              [],
+              "CMD" => %w[ruby gen.rb ${_TARGET}],
+              "CMD_DESC" => "Generating")
+  env["build_root"] = env.build_root
+  env["inc_c"] = "inc.c"
+  env.Object("program.o", "program.c")
+  env.build_after("program.o", "${inc_c}")
+  env.Program("program.exe", ["program.o", "inc.c"])
 end

build_tests/custom_builder/cvar_expansion.rb

@@ -9,12 +9,10 @@ EOF
   end
 end
 
-default do
-  env = Environment.new do |env|
-    env["hdr"] = "inc.h"
-    env["src"] = "program.c"
-    env.add_builder(MySource)
-    env.MySource('${hdr}')
-    env.Program('program.exe', "${src}")
-  end
+env = env do |env|
+  env["hdr"] = "inc.h"
+  env["src"] = "program.c"
+  env.add_builder(MySource)
+  env.MySource('${hdr}')
+  env.Program('program.exe', "${src}")
 end

build_tests/custom_builder/cvar_lambda.rb

@@ -9,22 +9,20 @@ EOF
   end
 end
 
-default do
-  e1 = Environment.new do |env|
-    env.add_builder(MySource)
-    env["one"] = "5"
-    env[:cfg] = {val: "9"}
-    env["two"] = lambda do |args|
-      args[:env][:cfg][:val]
-    end
-    env["the_value"] = lambda do |args|
-      "${one}${two}78"
-    end
+e1 = env do |env|
+  env.add_builder(MySource)
+  env["one"] = "5"
+  env[:cfg] = {val: "9"}
+  env["two"] = lambda do |args|
+    args[:env][:cfg][:val]
   end
-
-  e1.clone do |env|
-    env[:cfg][:val] = "6"
-    env.MySource('inc.h', [])
-    env.Program('program.exe', Dir['*.c'])
+  env["the_value"] = lambda do |args|
+    "${one}${two}78"
   end
 end
+
+e1.clone do |env|
+  env[:cfg][:val] = "6"
+  env.MySource('inc.h', [])
+  env.Program('program.exe', Dir['*.c'])
+end

build_tests/custom_builder/error_run_return_value.rb

@@ -1,8 +1,6 @@
-default do
-  Environment.new do |env|
-    env.add_builder(:MyBuilder) do |options|
-      "hi"
-    end
-    env.MyBuilder("foo")
+env do |env|
+  env.add_builder(:MyBuilder) do |options|
+    "hi"
   end
+  env.MyBuilder("foo")
 end

build_tests/custom_builder/error_wait_for.rb

@@ -1,8 +1,6 @@
-default do
-  Environment.new do |env|
-    env.add_builder(:MyBuilder) do |options|
-      wait_for(1)
-    end
-    env.MyBuilder("foo")
+env do |env|
+  env.add_builder(:MyBuilder) do |options|
+    wait_for(1)
   end
+  env.MyBuilder("foo")
 end

build_tests/custom_builder/multiple_targets.rb

@@ -12,10 +12,8 @@ class CHGen < Rscons::Builder
   end
 end
 
-default do
-  Environment.new do |env|
-    env.add_builder(CHGen)
-    env.CHGen("inc.c", ["program.c"])
-    env.Program("program.exe", %w[program.c inc.c])
-  end
+env do |env|
+  env.add_builder(CHGen)
+  env.CHGen("inc.c", ["program.c"])
+  env.Program("program.exe", %w[program.c inc.c])
 end

build_tests/custom_builder/produces.rb

@@ -1,17 +1,15 @@
-default do
-  Environment.new do |env|
-    env["build_root"] = env.build_root
-    env["inc_h"] = "inc.h"
+env do |env|
+  env["build_root"] = env.build_root
+  env["inc_h"] = "inc.h"
 
-    env.Copy("copy_inc.h", "${inc_h}")
-    env.depends("program.o", "${inc_h}")
-    env.Object("program.o", "program.c")
-    env.Program("program.exe", ["program.o", "inc.c"])
+  env.Copy("copy_inc.h", "${inc_h}")
+  env.depends("program.o", "${inc_h}")
+  env.Object("program.o", "program.c")
+  env.Program("program.exe", ["program.o", "inc.c"])
 
-    inc_c = env.Command("inc.c",
-                        [],
-                        "CMD" => %w[ruby gen.rb ${_TARGET}],
-                        "CMD_DESC" => "Generating")
-    inc_c.produces("inc.h")
-  end
+  inc_c = env.Command("inc.c",
+                      [],
+                      "CMD" => %w[ruby gen.rb ${_TARGET}],
+                      "CMD_DESC" => "Generating")
+  inc_c.produces("inc.h")
 end

build_tests/custom_builder/produces_env.rb

@@ -1,17 +1,15 @@
-default do
-  Environment.new do |env|
-    env["build_root"] = env.build_root
-    env["inc_h"] = "inc.h"
+env do |env|
+  env["build_root"] = env.build_root
+  env["inc_h"] = "inc.h"
 
-    env.Copy("copy_inc.h", "${inc_h}")
-    env.depends("program.o", "${inc_h}")
-    env.Object("program.o", "program.c")
-    env.Program("program.exe", ["program.o", "inc.c"])
+  env.Copy("copy_inc.h", "${inc_h}")
+  env.depends("program.o", "${inc_h}")
+  env.Object("program.o", "program.c")
+  env.Program("program.exe", ["program.o", "inc.c"])
 
-    env.Command("inc.c",
-                [],
-                "CMD" => %w[ruby gen.rb ${_TARGET}],
-                "CMD_DESC" => "Generating")
-    env.produces("inc.c", "inc.h")
-  end
+  env.Command("inc.c",
+              [],
+              "CMD" => %w[ruby gen.rb ${_TARGET}],
+              "CMD_DESC" => "Generating")
+  env.produces("inc.c", "inc.h")
 end

build_tests/custom_builder/wait_for_thread.rb

@@ -13,9 +13,7 @@ class MyBuilder < Rscons::Builder
   end
 end
 
-default do
-  Environment.new do |env|
-    env.add_builder(MyBuilder)
-    env.MyBuilder("foo")
-  end
+env do |env|
+  env.add_builder(MyBuilder)
+  env.MyBuilder("foo")
 end