1 files changed, 145 insertions, 0 deletions
diff --git a/main/test/src/define/MacroErrorTests.scala b/main/test/src/define/MacroErrorTests.scala
new file mode 100644
index 00000000..c8b140fa
--- /dev/null
+++ b/main/test/src/define/MacroErrorTests.scala
@@ -0,0 +1,145 @@
+package mill.define
+
+import utest._
+import mill.{T, Module}
+import mill.util.TestUtil
+object MacroErrorTests extends TestSuite{
+
+  val tests = Tests{
+
+    'errors{
+      val expectedMsg =
+        "T{} members must be defs defined in a Cacher class/trait/object body"
+
+      val err = compileError("object Foo extends TestUtil.BaseModule{ val x = T{1} }")
+      assert(err.msg == expectedMsg)
+    }
+
+    'badParameterSets - {
+      'command - {
+        val e = compileError("""
+          object foo extends mill.util.TestUtil.BaseModule{
+            def w = T.command{1}
+          }
+          mill.define.Discover[foo.type]
+        """)
+        assert(
+          e.msg.contains("`T.command` definitions must have 1 parameter list"),
+          e.pos.contains("def w = ")
+        )
+      }
+      'target - {
+        val e = compileError("""
+          object foo extends mill.util.TestUtil.BaseModule{
+            def x() = T{1}
+          }
+          mill.define.Discover[foo.type]
+        """)
+        assert(
+          e.msg.contains("`T{...}` definitions must have 0 parameter lists"),
+          e.pos.contains("def x() = ")
+        )
+      }
+      'input - {
+        val e = compileError("""
+          object foo extends mill.util.TestUtil.BaseModule{
+            def y() = T.input{1}
+          }
+          mill.define.Discover[foo.type]
+        """)
+        assert(
+          e.msg.contains("`T.input` definitions must have 0 parameter lists"),
+          e.pos.contains("def y() = ")
+        )
+      }
+      'sources - {
+        val e = compileError("""
+          object foo extends mill.util.TestUtil.BaseModule{
+            def z() = T.sources{ammonite.ops.pwd}
+          }
+          mill.define.Discover[foo.type]
+        """)
+        assert(
+          e.msg.contains("`T.sources` definitions must have 0 parameter lists"),
+          e.pos.contains("def z() = ")
+        )
+      }
+      'persistent - {
+        val e = compileError("""
+          object foo extends mill.util.TestUtil.BaseModule{
+            def a() = T.persistent{1}
+          }
+          mill.define.Discover[foo.type]
+        """)
+        assert(
+          e.msg.contains("`T.persistent` definitions must have 0 parameter lists"),
+          e.pos.contains("def a() = ")
+        )
+      }
+    }
+    'badTmacro - {
+      // Make sure we can reference values from outside the T{...} block as part
+      // of our `Target#apply()` calls, but we cannot reference any values that
+      // come from inside the T{...} block
+      'pos - {
+        val e = compileError("""
+          val a = T{ 1 }
+          val arr = Array(a)
+          val b = {
+            val c = 0
+            T{
+              arr(c)()
+            }
+          }
+        """)
+        assert(e.msg.contains(
+          "Modules, Targets and Commands can only be defined within a mill Module")
+        )
+      }
+      'neg - {
+
+        val expectedMsg =
+          "Target#apply() call cannot use `value n` defined within the T{...} block"
+        val err = compileError("""new Module{
+          def a = T{ 1 }
+          val arr = Array(a)
+          def b = {
+            T{
+              val n = 0
+              arr(n)()
+            }
+          }
+        }""")
+        assert(err.msg == expectedMsg)
+      }
+      'neg2 - {
+
+        val expectedMsg =
+          "Target#apply() call cannot use `value x` defined within the T{...} block"
+        val err = compileError("""new Module{
+          def a = T{ 1 }
+          val arr = Array(a)
+          def b = {
+            T{
+              arr.map{x => x()}
+            }
+          }
+        }""")
+        assert(err.msg == expectedMsg)
+      }
+      'neg3{
+        val borkedCachedDiamond1 = utest.compileError("""
+          object borkedCachedDiamond1 {
+            def up = T{ TestUtil.test() }
+            def left = T{ TestUtil.test(up) }
+            def right = T{ TestUtil.test(up) }
+            def down = T{ TestUtil.test(left, right) }
+          }
+        """)
+        assert(borkedCachedDiamond1.msg.contains(
+          "Modules, Targets and Commands can only be defined within a mill Module")
+        )
+      }
+    }
+  }
+}