From ac0f6087fc52cdcb2177c417a97b9a33886a5f9d Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Sun, 30 Jan 2022 13:11:47 -0500
Subject: [PATCH] Add Task#[]

---
 build_tests/tasks/tasks.rb |  8 ++++++++
 lib/rscons/task.rb         | 15 +++++++++++++++
 spec/build_tests_spec.rb   | 21 +++++++++++++++++++++
 3 files changed, 44 insertions(+)

diff --git a/build_tests/tasks/tasks.rb b/build_tests/tasks/tasks.rb
index c49ccea..dc2e3ec 100644
--- a/build_tests/tasks/tasks.rb
+++ b/build_tests/tasks/tasks.rb
@@ -18,3 +18,11 @@ task "four", desc: "Task four", params: [
   puts "myparam:" + params["myparam"].inspect
   puts "myp2:" + params["myp2"].inspect
 end
+
+task "five" do
+  puts "four myparam value is #{Task["four"]["myparam"]}"
+end
+
+task "six" do |task|
+  puts task["nope"]
+end
diff --git a/lib/rscons/task.rb b/lib/rscons/task.rb
index 6d34833..42da156 100644
--- a/lib/rscons/task.rb
+++ b/lib/rscons/task.rb
@@ -131,6 +131,21 @@ module Rscons
       modify(options, &block)
     end
 
+    # Get a parameter's value.
+    #
+    # @param param_name [String]
+    #   Parameter name.
+    #
+    # @return [String]
+    #   Parameter value.
+    def [](param_name)
+      param = @params[param_name]
+      unless param
+        raise RsconsError.new("Could not find parameter '#{param_name}'")
+      end
+      param.value
+    end
+
     # Execute a task's actions.
     #
     # @return [void]
diff --git a/spec/build_tests_spec.rb b/spec/build_tests_spec.rb
index 6aef8fe..6aa82ed 100644
--- a/spec/build_tests_spec.rb
+++ b/spec/build_tests_spec.rb
@@ -2885,6 +2885,27 @@ EOF
     expect(result.stdout).to eq %[four\nmyparam:"cli-value"\nmyp2:"--myp2"\none\n]
   end
 
+  it "allows accessing task arguments via Task#[]" do
+    test_dir "tasks"
+    result = run_rscons(args: %w[-f tasks.rb configure])
+    result = run_rscons(args: %w[-f tasks.rb five])
+    expect(result.stderr).to eq ""
+    expect(result.status).to eq 0
+    expect(result.stdout).to match /four myparam value is defaultvalue/
+    result = run_rscons(args: %w[-f tasks.rb four --myparam=v42 five])
+    expect(result.stderr).to eq ""
+    expect(result.status).to eq 0
+    expect(result.stdout).to match /four myparam value is v42/
+  end
+
+  it "exits with an error when attempting to get a nonexistent parameter value" do
+    test_dir "tasks"
+    result = run_rscons(args: %w[-f tasks.rb configure])
+    result = run_rscons(args: %w[-f tasks.rb six])
+    expect(result.stderr).to match /Could not find parameter 'nope'/
+    expect(result.status).to_not eq 0
+  end
+
   it "displays tasks and their arguments in the help info" do
     test_dir "tasks"
     result = run_rscons(args: %w[-f tasks.rb -h])