Add acceptance test 106 showing issue with if/is implicit casting.

examples/acceptance_tests/106/aiken.lock

@@ -0,0 +1,7 @@
+# This file was generated by Aiken
+# You typically do not need to edit this file
+
+requirements = []
+packages = []
+
+[etags]

examples/acceptance_tests/106/aiken.toml

@@ -0,0 +1,9 @@
+name = "aiken-lang/106"
+version = "0.0.0"
+license = "Apache-2.0"
+description = "Aiken contracts for project 'aiken-lang/106'"
+
+[repository]
+user = "aiken-lang"
+project = "106"
+platform = "github"

examples/acceptance_tests/106/lib/tests.ak

@@ -0,0 +1,62 @@
+type Foo {
+  foo: Int,
+}
+
+type Bar {
+  Buzz
+  Bazz
+}
+
+test soft_casting_1() {
+  let data: Data = Foo { foo: 42 }
+  if data is Foo {
+    True
+  } else {
+    False
+  }
+}
+
+test soft_casting_2() {
+  let data: Data = Foo { foo: 42 }
+  if data is Foo { .. }: Foo {
+    True
+  } else {
+    False
+  }
+}
+
+test soft_casting_3() {
+  let data: Data = Buzz
+  if data is Foo {
+    False
+  } else {
+    True
+  }
+}
+
+test soft_casting_4() {
+  let data: Data = Buzz
+  if data is Foo { .. }: Foo {
+    False
+  } else {
+    True
+  }
+}
+
+test soft_casting_5() {
+  let data: Data = Bazz
+  if data is Foo {
+    False
+  } else {
+    True
+  }
+}
+
+test soft_casting_6() {
+  let data: Data = Bazz
+  if data is Foo { .. }: Foo {
+    False
+  } else {
+    True
+  }
+}