From 56b5a711e478702e42c283ac7ba45f94b71785f0 Mon Sep 17 00:00:00 2001
From: Andy Meneely <andy@se.rit.edu>
Date: Thu, 17 Nov 2016 21:02:44 -0500
Subject: [PATCH] dsl: add Squib.configure

I ended up adding this one on a whim, but it feels like a long time coming. We need cleaner support for Rakefiles, and this is a good step toward that I think.
---
 CHANGELOG.md             |  1 +
 docs/config.rst          | 15 ++++++++++++++-
 docs/dsl/configure.rst   | 18 ++++++++++++++++++
 lib/squib/conf.rb        | 10 +++++++++-
 spec/conf_spec.rb        |  8 ++++++++
 spec/data/conf/basic.yml |  1 +
 6 files changed, 51 insertions(+), 2 deletions(-)
 create mode 100644 docs/dsl/configure.rst

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a003e89..918a3e1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@ Squib follows [semantic versioning](http://semver.org).
 
 Features:
 * `save_pdf` now supports crop marks! These are lines drawn in the margins of a PDF file to help you cut. These can be enabled by setting `crop_marks: true` in your `save_pdf` call. Can be further customized with `crop_margin_bottom`, `crop_margin_left`, `crop_margin_right`, `crop_margin_top`, `crop_marks`, `crop_stroke_color`, `crop_stroke_dash`, and `crop_stroke_width` (#123)
+* `Squib.configure` allows you to set options programmatically, overriding your config.yml. This is useful for Rakefiles, and will be documented in my upcoming tutorial on workflows.
 
 Bugs:
 * `showcase` works as expected when using `backend: svg` (#179)
diff --git a/docs/config.rst b/docs/config.rst
index f17ea62..28dd65f 100644
--- a/docs/config.rst
+++ b/docs/config.rst
@@ -47,7 +47,7 @@ prefix
 
 img_dir
   default: ``'.'``
-  
+
   For reading image file command (e.g. png and svg), read from this directory instead
 
 warn_ellipsize
@@ -111,6 +111,19 @@ For debugging/sanity purposes, if you want to make sure your configuration optio
     puts backend # prints 'memory' by default
   end
 
+These are read-only - you will not be able to change these.
+
+Squib.configure sets options programmatically
+---------------------------------------------
+
+You can also use :doc:`/dsl/configure` to override anything in the config file. Use it like this:
+
+.. literalinclude:: ../samples/project/Rakefile
+  :language: ruby
+  :linenos:
+
+
+See :doc:`/guides/getting-started/part_3_workflows` for how we put this to good use.
 
 Making Squib Verbose
 --------------------
diff --git a/docs/dsl/configure.rst b/docs/dsl/configure.rst
new file mode 100644
index 0000000..74fe7e1
--- /dev/null
+++ b/docs/dsl/configure.rst
@@ -0,0 +1,18 @@
+Squib.configure
+---------------
+
+Prior to the construction of a Squib::Deck, set a global default that overrides what is specified `config.yml`.
+
+This is intended to be done prior to Squib::Deck.new, and is intended to be used inside of a Rakefile
+
+Options
+^^^^^^^
+
+All options that are specified in :doc:`/config`
+
+Exmaples
+^^^^^^^^
+
+.. literalinclude:: ../../samples/project/Rakefile
+  :language: ruby
+  :linenos:
diff --git a/lib/squib/conf.rb b/lib/squib/conf.rb
index ceeed58..9875bc7 100644
--- a/lib/squib/conf.rb
+++ b/lib/squib/conf.rb
@@ -3,6 +3,14 @@ require 'yaml'
 require_relative 'args/typographer'
 
 module Squib
+  USER_CONFIG = {}
+
+  def configure(opts)
+    str_hash = opts.inject({}) { |h, (k, v)| h[k.to_s] = v; h }
+    USER_CONFIG.merge! str_hash
+  end
+  module_function :configure
+
   # @api private
   class Conf
 
@@ -40,7 +48,7 @@ module Squib
     }
 
     def initialize(config_hash = DEFAULTS)
-      @config_hash = config_hash
+      @config_hash = config_hash.merge USER_CONFIG # programmatic overrides yml
       @typographer = Args::Typographer.new(config_hash)
       normalize_antialias
     end
diff --git a/spec/conf_spec.rb b/spec/conf_spec.rb
index 87295aa..68df488 100644
--- a/spec/conf_spec.rb
+++ b/spec/conf_spec.rb
@@ -36,4 +36,12 @@ describe Squib::Conf do
     expect(conf.to_s).to start_with 'Conf: '
   end
 
+  it 'allows Squib.configure to override yml' do
+    Squib.configure img_dir: 'color'
+    c = Squib::Conf.load conf('basic.yml')
+    expect(c.img_dir).to eq 'color'
+    # reset our state to be nice
+    Squib::USER_CONFIG.clear
+  end
+
 end
diff --git a/spec/data/conf/basic.yml b/spec/data/conf/basic.yml
index e69de29..62a27e8 100644
--- a/spec/data/conf/basic.yml
+++ b/spec/data/conf/basic.yml
@@ -0,0 +1 @@
+img_dir: bw