clean up tests/

give helper function a more descriptive name

Cargo.lock

@@ -9,6 +9,20 @@ dependencies = [
  "nodrop",
 ]
 
+[[package]]
+name = "assert_cmd"
+version = "1.0.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f2475b58cd94eb4f70159f4fd8844ba3b807532fe3131b3373fae060bbe30396"
+dependencies = [
+ "bstr",
+ "doc-comment",
+ "predicates",
+ "predicates-core",
+ "predicates-tree",
+ "wait-timeout",
+]
+
 [[package]]
 name = "autocfg"
 version = "0.1.7"
@@ -87,6 +101,17 @@ dependencies = [
  "byte-tools",
 ]
 
+[[package]]
+name = "bstr"
+version = "0.2.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a40b47ad93e1a5404e6c18dec46b628214fee441c70f4ab5d6942142cc268a3d"
+dependencies = [
+ "lazy_static",
+ "memchr",
+ "regex-automata",
+]
+
 [[package]]
 name = "bumpalo"
 version = "3.6.0"
@@ -206,6 +231,12 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "difference"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "524cbf6897b527295dff137cec09ecf3a05f4fddffd7dfcd1585403449e74198"
+
 [[package]]
 name = "digest"
 version = "0.8.1"
@@ -242,6 +273,12 @@ version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bc9f8914dcb99891bdfee82536bbff8d9aa612b0dbe83872afbc66902bdec0b9"
 
+[[package]]
+name = "doc-comment"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fea41bba32d969b513997752735605054bc0dfa92b4c56bf1189f2e174be7a10"
+
 [[package]]
 name = "downcast"
 version = "0.10.0"
@@ -851,6 +888,32 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "925383efa346730478fb4838dbe9137d2a47675ad789c546d150a6e1dd4ab31c"
 
+[[package]]
+name = "predicates"
+version = "1.0.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eeb433456c1a57cc93554dea3ce40b4c19c4057e41c55d4a0f3d84ea71c325aa"
+dependencies = [
+ "difference",
+ "predicates-core",
+]
+
+[[package]]
+name = "predicates-core"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "57e35a3326b75e49aa85f5dc6ec15b41108cf5aee58eabb1f274dd18b73c2451"
+
+[[package]]
+name = "predicates-tree"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "15f553275e5721409451eb85e15fd9a860a6e5ab4496eb215987502b5f5391f2"
+dependencies = [
+ "predicates-core",
+ "treeline",
+]
+
 [[package]]
 name = "proc-macro-hack"
 version = "0.5.19"
@@ -1091,6 +1154,15 @@ version = "0.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d813022b2e00774a48eaf43caaa3c20b45f040ba8cbf398e2e8911a06668dbe6"
 
+[[package]]
+name = "regex-automata"
+version = "0.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ae1ded71d66a4a97f5e961fd0cb25a5f366a42a41570d16a763a69c092c26ae4"
+dependencies = [
+ "byteorder",
+]
+
 [[package]]
 name = "remove_dir_all"
 version = "0.5.3"
@@ -1202,6 +1274,7 @@ checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
 name = "scryer-prolog"
 version = "0.8.128"
 dependencies = [
+ "assert_cmd",
  "base64",
  "blake2",
  "chrono",
@@ -1220,6 +1293,7 @@ dependencies = [
  "num-rug-adapter",
  "openssl",
  "ordered-float",
+ "predicates-core",
  "prolog_parser",
  "ref_thread_local",
  "ring",
@@ -1492,6 +1566,12 @@ dependencies = [
  "winapi 0.3.9",
 ]
 
+[[package]]
+name = "treeline"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a7f741b240f1a48843f9b8e0444fb55fb2a4ff67293b50a9179dfd5ea67f8d41"
+
 [[package]]
 name = "typenum"
 version = "1.12.0"
@@ -1571,6 +1651,15 @@ version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
 
+[[package]]
+name = "wait-timeout"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9f200f5b12eb75f8c1ed65abd4b2db8a6e1b138a20de009dacee265a2498f3f6"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "wasi"
 version = "0.10.2+wasi-snapshot-preview1"