Handle multiple extracted versions of same webjar

build.sbt

@@ -14,15 +14,9 @@ developers += Developer(
 )
 
 libraryDependencies ++= Seq(
-  "org.webjars.npm" % "jshint" % "2.13.6",
-
-  // Multiple strip-json-comments dependencies will be downloaded by webjars extractor.
-  // Therefore we need to add the version we want to use to the require(...) statement.
-  // E.g. when running the scripted test by hand you will find the webjars in:
-  // src/sbt-test/sbt-jshint-plugin/test$ ls -a1 ./project/target/node-modules/webjars/strip-json-comments/
-  // 1.0.2-1
-  // 1.0.4
-  "org.webjars" % "strip-json-comments" % "1.0.2-1" // sync with "var stripJsonComments = require(...)" in src/main/resources/jshint-shell.js
+  "org.webjars.npm" % "node-require-fallback" % "1.0.0",
+  "org.webjars.npm" % "jshint" % "2.13.6", // sync with src/main/resources/jshint-shell.js
+  "org.webjars" % "strip-json-comments" % "1.0.2-1", // sync with src/main/resources/jshint-shell.js
 )
 
 addSbtJsEngine("1.3.5")

src/main/resources/jshint-shell.js

@@ -19,10 +19,11 @@
     "use strict";
 
     var args = process.argv;
+    var requireIfExists = require('node-require-fallback');
     var console = require("console");
     var fs = require("fs");
-    var jshint = require("jshint");
-    var stripJsonComments = require("strip-json-comments/1.0.2-1"); // version of sub-folder defined in build.sbt's libraryDependencies
+    var jshint = requireIfExists("jshint/2.13.6", "jshint"); // sync with build.sbt
+    var stripJsonComments = requireIfExists("strip-json-comments/1.0.2-1", "strip-json-comments"); // sync with build.sbt
 
     var SOURCE_FILE_MAPPINGS_ARG = 2;
     var OPTIONS_ARG = 4;

src/sbt-test/sbt-jshint-plugin/test-same-webjars-different-version/build.sbt

@@ -0,0 +1,4 @@
+lazy val root = (project in file(".")).enablePlugins(SbtWeb)
+
+WebKeys.reporter := new TestBuild.TestReporter(target.value)
+

src/sbt-test/sbt-jshint-plugin/test-same-webjars-different-version/project/TestBuild.scala

@@ -0,0 +1,21 @@
+import sbt._
+import java.util.function.Supplier
+
+object TestBuild {
+
+  class TestLogger(target: File) extends xsbti.Logger {
+
+    def error(msg: Supplier[String]): Unit = {
+      if (msg.get().contains("Missing semicolon.")) {
+        IO.touch(target / "missing-semi-error")
+      }
+    }
+
+    def warn(msg: Supplier[String]): Unit = {}
+    def info(msg: Supplier[String]): Unit = {}
+    def debug(msg: Supplier[String]): Unit = {}
+    def trace(t: Supplier[Throwable]): Unit = {}
+  }
+
+  class TestReporter(target: File) extends sbt.internal.inc.LoggedReporter(-1, new TestLogger(target))
+}

src/sbt-test/sbt-jshint-plugin/test-same-webjars-different-version/project/plugins.sbt

@@ -0,0 +1,21 @@
+addSbtPlugin("com.github.sbt" % "sbt-jshint" % sys.props("project.version"))
+
+// When the same webjar (= same name) from different groupIds (org.webjars[.npm|bower]?)
+// are are on the classpath, those webjars get extracted into subfolders which are named by the version of the webjar.
+// However, if there is just one type (npm, bower, classic) of a webjar on the classpath, NO subfolders gets created.
+// Now, because in a project we don't know which other webjars get pulled in from other dependencies, it can happen
+// that subfolders get created, or may not. However, require(...) can't know that and therefore has to look in both places.
+// To test that the lookup is correct, we force this scripted test to create subfolders by pulling in the same webjar
+// but from different groupIds (the other scripted test does not do that and therefore no subfolders get created there)
+// btw: dependency eviction within the same type of webjar still works correctly, so e.g. 0.2 wins over 0.1 within the same type of webjar
+// and no subfolder will be forced for that case but the newest version will be choosen. Like normal dependency resolution.
+libraryDependencies ++= Seq(
+  // Pulling in the classic and the npm webjar to subfolders for this webjar will be created
+  "org.webjars.npm" % "jshint" % "2.9.7",
+  "org.webjars" % "jshint" % "2.9.1",
+
+  // Same here, we pull in the bower and the npm one so subfolders will be created
+  // ("1.9.2/ and 2.5.1 etc.)
+  "org.webjars" % "strip-json-comments" % "1.0.2",
+  "org.webjars.npm" % "strip-json-comments" % "0.1.1",
+)

src/sbt-test/sbt-jshint-plugin/test-same-webjars-different-version/src/main/assets/some.js

@@ -0,0 +1,3 @@
+function a() {
+    return 1
+}

src/sbt-test/sbt-jshint-plugin/test-same-webjars-different-version/test

@@ -0,0 +1,12 @@
+# Lint an valid js file and see that linting errors are reported.
+-> assets
+$ exists target/missing-semi-error
+
+> set JshintKeys.config := Some(file("test.jshintrc"))
+> assets
+
+$ exists project/target/node-modules/webjars/jshint/2.13.6/bin/jshint
+$ exists project/target/node-modules/webjars/jshint/2.9.1/jshint.js
+
+$ exists project/target/node-modules/webjars/strip-json-comments/1.0.2-1/strip-json-comments.js
+$ exists project/target/node-modules/webjars/strip-json-comments/1.0.4/strip-json-comments.js

src/sbt-test/sbt-jshint-plugin/test-same-webjars-different-version/test.jshintrc

@@ -0,0 +1,3 @@
+{
+    "asi"           : true
+}

src/sbt-test/sbt-jshint-plugin/test/project/plugins.sbt

@@ -1,6 +1 @@
-resolvers ++= Seq(
-    Resolver.mavenLocal,
-    Resolver.sonatypeRepo("snapshots"),
-    )
-
 addSbtPlugin("com.github.sbt" % "sbt-jshint" % sys.props("project.version"))

src/sbt-test/sbt-jshint-plugin/test/test

@@ -4,3 +4,8 @@ $ exists target/missing-semi-error
 
 > set JshintKeys.config := Some(file("test.jshintrc"))
 > assets
+
+$ exists project/target/node-modules/webjars/jshint/bin/jshint
+
+$ exists project/target/node-modules/webjars/strip-json-comments/1.0.2-1/strip-json-comments.js
+$ exists project/target/node-modules/webjars/strip-json-comments/1.0.4/strip-json-comments.js