Anchor sbt plugin detection on ": enabled in"

`sbt plugins` lists user-disabled plugins (`disablePlugins(...)`) with
a ": disabled in <scope>" suffix. The pre-existing substring match on
the bare FQCN counted those as present, which routed `findProjects`
to a task the active plugin set does not provide — same shape as the
TKT-15490 regression, different trigger.

Detection now requires "<FQCN>: enabled in" verbatim. Fixtures cover
the two disabled cases (mini disabled, modern disabled), both
expected to classify as Nothing.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: zlav

src/Strategy/Scala/Plugin.hs

@@ -70,18 +70,24 @@ hasDependencyPlugins projectDir = do
 --      used on sbt < 1.4. Provides the lowercase @dependencyBrowseTreeHtml@
 --      task.
 --
+-- Detection anchors on the @\<FQCN\>: enabled in@ suffix rather than the bare
+-- FQCN. @sbt plugins@ lists plugins the user has explicitly disabled (via
+-- @disablePlugins(...)@) with @: disabled in \<scope\>@ — those still
+-- contain the FQCN as a substring, so an unanchored match would wrongly
+-- route to a task that doesn't exist on the active plugin set.
+--
 -- When both modern and legacy non-mini plugins are present we prefer the
 -- modern one (sbt 1.4+ wins) since legacy plugin presence on a modern sbt
 -- typically means the user has both kinds of declarations in their build.
 detectDependencyPlugins :: Text -> DependencyPluginsDetected
 detectDependencyPlugins stdoutText =
   DependencyPluginsDetected
-    { hasMiniDependencyTreePlugin = Text.count ".MiniDependencyTreePlugin" stdoutText > 0
+    { hasMiniDependencyTreePlugin = "sbt.plugins.MiniDependencyTreePlugin: enabled in" `Text.isInfixOf` stdoutText
     , dependencyTreePlugin =
-        if Text.count "sbt.plugins.DependencyTreePlugin" stdoutText > 0
+        if "sbt.plugins.DependencyTreePlugin: enabled in" `Text.isInfixOf` stdoutText
           then Just ModernDependencyTreePlugin
           else
-            if Text.count "net.virtualvoid.sbt.graph.DependencyGraphPlugin" stdoutText > 0
+            if "net.virtualvoid.sbt.graph.DependencyGraphPlugin: enabled in" `Text.isInfixOf` stdoutText
               then Just LegacyDependencyGraphPlugin
               else Nothing
     }

test/Scala/PluginSpec.hs

@@ -59,6 +59,18 @@ spec = do
       detectDependencyPlugins sbtNoPlugins
         `shouldBe` DependencyPluginsDetected{hasMiniDependencyTreePlugin = False, dependencyTreePlugin = Nothing}
 
+    -- `sbt plugins` lists user-disabled plugins (`disablePlugins(...)`) with a
+    -- ": disabled in <scope>" suffix. The FQCN still appears on those lines,
+    -- so detection must anchor on ": enabled in" to avoid routing to a task
+    -- the active plugin set doesn't provide.
+    it "should not treat MiniDependencyTreePlugin as present when listed as disabled" $ do
+      detectDependencyPlugins sbtDisabledMiniPlugin
+        `shouldBe` DependencyPluginsDetected{hasMiniDependencyTreePlugin = False, dependencyTreePlugin = Nothing}
+
+    it "should not treat modern DependencyTreePlugin as present when listed as disabled" $ do
+      detectDependencyPlugins sbtDisabledModernPlugin
+        `shouldBe` DependencyPluginsDetected{hasMiniDependencyTreePlugin = False, dependencyTreePlugin = Nothing}
+
 -- sbt 1.4+ with only built-in plugin
 sbt14BuiltinOnly :: Text
 sbt14BuiltinOnly =
@@ -165,3 +177,28 @@ sbtNoPlugins =
 [info]   sbt.plugins.IvyPlugin: enabled in root
 [info]   sbt.plugins.JvmPlugin: enabled in root
 |]
+
+-- User-disabled MiniDependencyTreePlugin (e.g. `disablePlugins(MiniDependencyTreePlugin)`
+-- in build.sbt). The FQCN appears on a ": disabled in" line — detection
+-- must reject it.
+sbtDisabledMiniPlugin :: Text
+sbtDisabledMiniPlugin =
+  [r|[info] welcome to sbt 1.9.7 (Eclipse Adoptium Java 11.0.21)
+[info] In file:/Users/test/project/
+[info]   sbt.plugins.CorePlugin: enabled in root
+[info]   sbt.plugins.IvyPlugin: enabled in root
+[info]   sbt.plugins.JvmPlugin: enabled in root
+[info]   sbt.plugins.MiniDependencyTreePlugin: disabled in root
+|]
+
+-- User-disabled modern DependencyTreePlugin. Routing to the uppercase task
+-- would fail because the plugin isn't active.
+sbtDisabledModernPlugin :: Text
+sbtDisabledModernPlugin =
+  [r|[info] welcome to sbt 1.11.5 (Eclipse Adoptium Java 17.0.10)
+[info] In file:/Users/test/project/
+[info]   sbt.plugins.CorePlugin: enabled in root
+[info]   sbt.plugins.IvyPlugin: enabled in root
+[info]   sbt.plugins.JvmPlugin: enabled in root
+[info]   sbt.plugins.DependencyTreePlugin: disabled in root
+|]