Add support for script test definitions

spec/changelog.yml

@@ -17,6 +17,9 @@
     - description: Input packages don't require to define fields.
       type: enhancement
       link: https://github.com/elastic/package-spec/pull/994
+    - description: Add support for script testing in data streams.
+      type: enhancement
+      link: https://github.com/elastic/package-spec/pull/985
 - version: 3.5.0
   changes:
     - description: Add `duration` variable data type with `min_duration` and `max_duration` validation properties.

spec/integration/data_stream/_dev/test/scripts/spec.yml

@@ -0,0 +1,12 @@
+spec:
+  additionalContents: false
+  contents:
+    - description: >-
+        Script test definitions in txtar format, with semantics based on the
+        testscript package, but with extensions to make it possible to interact
+        with an Elastic stack. You can read more about the use of txtar and
+        testscript at https://pkg.go.dev/github.com/rogpeppe/go-internal/testscript.
+      type: file
+      contentMediaType: "text/plain"
+      pattern: '^.+\.(txt|txtar)$'
+      required: false

spec/integration/data_stream/_dev/test/spec.yml

@@ -21,3 +21,8 @@ spec:
       name: policy
       required: false
       $ref: "./policy/spec.yml"
+    - description: Folder containing script tests
+      type: folder
+      name: scripts
+      required: false
+      $ref: "./scripts/spec.yml"

test/packages/good_v3/data_stream/script_tests/_dev/test/scripts/env.txt

@@ -0,0 +1,59 @@
+[!exec:echo] skip 'Skipping test requiring absent echo command'
+
+exec echo ${PKG}
+stdout '^with_script$'
+
+exec echo ${PKG_ROOT}
+stdout 'github\.com/elastic/elastic-package/test/packages/other/with_script$'
+
+exec echo ${DATA_STREAM}
+stdout '^first$'
+
+exec echo ${DATA_STREAM_ROOT}
+stdout 'github\.com/elastic/elastic-package/test/packages/other/with_script/data_stream/first$'
+
+exec echo ${CURRENT_VERSION}
+stdout '^0\.0\.2$'
+
+exec echo ${PREVIOUS_VERSION}
+stdout '^0\.0\.1$'
+
+exec echo ${FIELDS_QUERY}
+cmp stdout want_query.text
+
+-- want_query.text --
+{
+  "fields": [
+    "*"
+  ],
+  "runtime_mappings": {
+    "my_ignored": {
+      "type": "keyword",
+      "script": {
+        "source": "for (def v : params['_fields']._ignored.values) { emit(v); }"
+      }
+    }
+  },
+  "aggs": {
+    "all_ignored": {
+      "filter": {
+        "exists": {
+          "field": "_ignored"
+        }
+      },
+      "aggs": {
+        "ignored_fields": {
+          "terms": {
+            "size": 100,
+            "field": "my_ignored"
+          }
+        },
+        "ignored_docs": {
+          "top_hits": {
+            "size": 5
+          }
+        }
+      }
+    }
+  }
+}

test/packages/good_v3/data_stream/script_tests/_dev/test/scripts/noop.txt

@@ -0,0 +1 @@
+# This is a noop test.

test/packages/good_v3/data_stream/script_tests/_dev/test/scripts/noop.txtar

@@ -0,0 +1 @@
+# This is a noop test.

test/packages/good_v3/data_stream/script_tests/fields/base-fields.yml

@@ -0,0 +1,12 @@
+- name: data_stream.type
+  type: constant_keyword
+  description: Data stream type.
+- name: data_stream.dataset
+  type: constant_keyword
+  description: Data stream dataset.
+- name: data_stream.namespace
+  type: constant_keyword
+  description: Data stream namespace.
+- name: '@timestamp'
+  type: date
+  description: Event timestamp.

test/packages/good_v3/data_stream/script_tests/fields/some_fields.yml

@@ -0,0 +1,28 @@
+- name: source
+  title: Source
+  group: 2
+  type: group
+  fields:
+    - name: geo.city_name
+      level: core
+      type: keyword
+      description: City name.
+      ignore_above: 1024
+    - name: geo.location
+      level: core
+      type: geo_point
+      description: Longitude and latitude.
+    - name: geo.region_iso_code
+      level: core
+      type: keyword
+      description: Region ISO code.
+      ignore_above: 1024
+    - name: geo.region_name
+      level: core
+      type: keyword
+      description: Region name.
+      ignore_above: 1024
+- name: foobar
+  type: text
+  description: A field with a pattern defined
+  pattern: '^[a-zA-Z]$'

test/packages/good_v3/data_stream/script_tests/manifest.yml

@@ -0,0 +1,2 @@
+title: Package with script tests
+type: metrics