Support fallback strategies by setting array in config

spec/integrations/zle_input_stack_spec.rb

@@ -2,7 +2,7 @@ describe 'using `zle -U`' do
   let(:before_sourcing) do
     -> do
       session.
-        run_command('_zsh_autosuggest_strategy_test() { sleep 1; _zsh_autosuggest_strategy_default "$1" }').
+        run_command('_zsh_autosuggest_strategy_test() { sleep 1; _zsh_autosuggest_strategy_history "$1" }').
         run_command('foo() { zle -U - "echo hello" }; zle -N foo; bindkey ^B foo')
     end
   end

spec/options/strategy_spec.rb

@@ -1,20 +1,45 @@
 describe 'a suggestion for a given prefix' do
-  let(:options) { ['_zsh_autosuggest_strategy_default() { suggestion="echo foo" }'] }
+  let(:history_strategy) { '_zsh_autosuggest_strategy_history() { suggestion="history" }' }
+  let(:foobar_strategy) { '_zsh_autosuggest_strategy_foobar() { [[ "foobar baz" = $1* ]] && suggestion="foobar baz" }' }
+  let(:foobaz_strategy) { '_zsh_autosuggest_strategy_foobaz() { [[ "foobaz bar" = $1* ]] && suggestion="foobaz bar" }' }
 
-  it 'is determined by calling the default strategy function' do
-    session.send_string('e')
-    wait_for { session.content }.to eq('echo foo')
+  let(:options) { [ history_strategy ] }
+
+  it 'by default is determined by calling the `history` strategy function' do
+    session.send_string('h')
+    wait_for { session.content }.to eq('history')
   end
 
-  context 'when ZSH_AUTOSUGGEST_STRATEGY is set' do
+  context 'when ZSH_AUTOSUGGEST_STRATEGY is set to an array' do
     let(:options) { [
-      '_zsh_autosuggest_strategy_custom() { suggestion="echo foo" }',
-      'ZSH_AUTOSUGGEST_STRATEGY=custom'
+      foobar_strategy,
+      foobaz_strategy,
+      'ZSH_AUTOSUGGEST_STRATEGY=(foobar foobaz)'
     ] }
 
-    it 'is determined by calling the specified strategy function' do
-      session.send_string('e')
-      wait_for { session.content }.to eq('echo foo')
+    it 'is determined by the first strategy function to return a suggestion' do
+      session.send_string('foo')
+      wait_for { session.content }.to eq('foobar baz')
+
+      session.send_string('baz')
+      wait_for { session.content }.to eq('foobaz bar')
+    end
+  end
+
+  context 'when ZSH_AUTOSUGGEST_STRATEGY is set to a string' do
+    let(:options) { [
+      foobar_strategy,
+      foobaz_strategy,
+      'ZSH_AUTOSUGGEST_STRATEGY="foobar foobaz"'
+    ] }
+
+    it 'is determined by the first strategy function to return a suggestion' do
+      session.send_string('foo')
+      wait_for { session.content }.to eq('foobar baz')
+
+      session.send_string('baz')
+      wait_for { session.content }.to eq('foobaz bar')
     end
   end
 end
+