Write system tests for lobster-json regarding directory input

- Add a requirement to specify the behavior when a directory is specified as input
- Add system tests

tests-system/lobster-json/rbt-directory-input/non-json-input/expected-output/exit-code.txt

@@ -0,0 +1 @@
+0

tests-system/lobster-json/rbt-directory-input/non-json-input/expected-output/output.lobster

@@ -0,0 +1,24 @@
+{
+  "data": [
+    {
+      "tag": "json ./file.json:tree on island",
+      "location": {
+        "kind": "file",
+        "file": "./file.json",
+        "line": null,
+        "column": null
+      },
+      "name": "./file.json:tree on island",
+      "messages": [],
+      "just_up": [],
+      "just_down": [],
+      "just_global": [],
+      "framework": "JSON",
+      "kind": "Test Vector",
+      "status": null
+    }
+  ],
+  "generator": "lobster-json",
+  "schema": "lobster-act-trace",
+  "version": 3
+}

tests-system/lobster-json/rbt-directory-input/non-json-input/expected-output/stdout.txt

@@ -0,0 +1 @@
+lobster-json: wrote 1 items to output.lobster

tests-system/lobster-json/rbt-directory-input/non-json-input/input/args.txt

@@ -0,0 +1,5 @@
+--single
+--tag-attribute=something
+--name-attribute=name
+--out=output.lobster
+dir1

tests-system/lobster-json/rbt-directory-input/two-level-nesting/expected-output/exit-code.txt

@@ -0,0 +1 @@
+0

tests-system/lobster-json/rbt-directory-input/two-level-nesting/expected-output/output.lobster

@@ -0,0 +1,58 @@
+{
+  "data": [
+    {
+      "tag": "json ./dir1/dir2/deeply-nested.json:dir1.dir2.deeply-nested.1",
+      "location": {
+        "kind": "file",
+        "file": "./dir1/dir2/deeply-nested.json",
+        "line": null,
+        "column": null
+      },
+      "name": "./dir1/dir2/deeply-nested.json:dir1.dir2.deeply-nested.1",
+      "messages": [],
+      "just_up": [],
+      "just_down": [],
+      "just_global": [],
+      "framework": "JSON",
+      "kind": "Test Vector",
+      "status": null
+    },
+    {
+      "tag": "json ./dir1/nested.json:dir1.nested.1",
+      "location": {
+        "kind": "file",
+        "file": "./dir1/nested.json",
+        "line": null,
+        "column": null
+      },
+      "name": "./dir1/nested.json:dir1.nested.1",
+      "messages": [],
+      "just_up": [],
+      "just_down": [],
+      "just_global": [],
+      "framework": "JSON",
+      "kind": "Test Vector",
+      "status": null
+    },
+    {
+      "tag": "json ./file.json:file.1",
+      "location": {
+        "kind": "file",
+        "file": "./file.json",
+        "line": null,
+        "column": null
+      },
+      "name": "./file.json:file.1",
+      "messages": [],
+      "just_up": [],
+      "just_down": [],
+      "just_global": [],
+      "framework": "JSON",
+      "kind": "Test Vector",
+      "status": null
+    }
+  ],
+  "generator": "lobster-json",
+  "schema": "lobster-act-trace",
+  "version": 3
+}

tests-system/lobster-json/rbt-directory-input/two-level-nesting/expected-output/stdout.txt

@@ -0,0 +1 @@
+lobster-json: wrote 3 items to output.lobster

tests-system/lobster-json/rbt-directory-input/two-level-nesting/input/args.txt

@@ -0,0 +1,3 @@
+--single
+--tag-attribute=something
+--out=output.lobster

tests-system/lobster-json/rbt-directory-input/two-level-nesting/input/dir1/dir2/deeply-nested.json

@@ -0,0 +1,9 @@
+{
+  "cherry": {
+    "data": [
+      {
+        "name": "element three"
+      }
+    ]
+  }
+}

tests-system/lobster-json/rbt-directory-input/two-level-nesting/input/dir1/nested.json

@@ -0,0 +1,9 @@
+{
+  "banana": {
+    "data": [
+      {
+        "name": "element two"
+      }
+    ]
+  }
+}

tests-system/lobster-json/rbt-directory-input/two-level-nesting/input/file.json

@@ -0,0 +1,9 @@
+{
+  "apple": {
+    "data": [
+      {
+        "name": "element one"
+      }
+    ]
+  }
+}

tests-system/lobster-json/rbt-parse-input-file-input-items/outer-and-inner/README.md

@@ -0,0 +1,3 @@
+The input file of this test defines a JSON data struct which has got data items in its
+outer-most dictionary, as well as nested items.
+According to the requirement only the data items from the outer-most dictionary must be considered.

tests-system/lobster-json/rbt-parse-input-file-input-items/outer-and-inner/expected-output/exit-code.txt

@@ -0,0 +1 @@
+0

tests-system/lobster-json/rbt-parse-input-file-input-items/outer-and-inner/expected-output/stdout.txt

@@ -0,0 +1 @@
+lobster-json: wrote 1 items to output.lobster

tests-system/lobster-json/rbt-parse-input-file-input-items/outer-and-inner/input/args.txt

@@ -0,0 +1,3 @@
+--single
+--tag-attribute=something
+--out=output.lobster

tests-system/lobster-json/rbt-parse-input-file-input-items/outer-and-inner/input/data.json

@@ -0,0 +1,25 @@
+{
+    "outer1": {
+      "data": [
+        {
+          "name": "Take this item!"
+        },
+        {
+
+            "name": "unclear"
+        }
+      ]
+    },
+    "outer2": {
+        "data": [
+          {
+            "name": "Take this item!"
+          },
+          {
+
+              "name": "unclear"
+          }
+        ]
+      }
+  }
+