Give a deprecation message even when the lookup fails

If the supplied string doesn't contain a colon, it clearly cannot be a
database URL. They must have intended to do a key lookup, so even though
it failed, give the explanatory deprecation warning, and raise the
exception that lists the known configs.

Conveniently, this also simplifies our logical behaviour: if the string
matches a known configuration, or doesn't contain a colon (and is
therefore clearly not a URL), then we output a deprecation warning, and
behave exactly as we would if it were a symbol.

2 files changed, 6 insertions, 4 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/connection_specification.rb b/activerecord/lib/active_record/connection_adapters/connection_specification.rb
index e0715f7ce9..0cc92fa397 100644
--- a/activerecord/lib/active_record/connection_adapters/connection_specification.rb
+++ b/activerecord/lib/active_record/connection_adapters/connection_specification.rb
@@ -220,10 +220,10 @@ module ActiveRecord
           # an environment key or a URL spec, so we have deprecated
           # this ambiguous behaviour and in the future this function
           # can be removed in favor of resolve_url_connection.
-          if configurations.key?(spec)
+          if configurations.key?(spec) || spec !~ /:/
             ActiveSupport::Deprecation.warn "Passing a string to ActiveRecord::Base.establish_connection " \
               "for a configuration lookup is deprecated, please pass a symbol (#{spec.to_sym.inspect}) instead"
-            resolve_connection(configurations[spec])
+            resolve_symbol_connection(spec)
           else
             resolve_url_connection(spec)
           end
diff --git a/activerecord/test/cases/connection_adapters/connection_handler_test.rb b/activerecord/test/cases/connection_adapters/connection_handler_test.rb
index ae4172f15c..dd03f57f19 100644
--- a/activerecord/test/cases/connection_adapters/connection_handler_test.rb
+++ b/activerecord/test/cases/connection_adapters/connection_handler_test.rb
@@ -89,8 +89,10 @@ module ActiveRecord
       def test_resolver_with_database_uri_and_unknown_string_key
         ENV['DATABASE_URL'] = "postgres://localhost/foo"
         config   = { "not_production" => {  "adapter" => "not_postgres", "database" => "not_foo" } }
-        assert_raises AdapterNotSpecified do
-          spec("production", config)
+        assert_deprecated do
+          assert_raises AdapterNotSpecified do
+            spec("production", config)
+          end
         end
       end