Add version() function

.Rbuildignore

@@ -10,3 +10,5 @@
 ^pkgdown$
 ^README\.Rmd$
 ^CRAN-SUBMISSION$
+^\.positai$
+^\.claude$

.gitignore

@@ -46,3 +46,4 @@ docs
 
 # Mac OS
 .DS_Store
+.positai

NAMESPACE

@@ -14,6 +14,7 @@ export(remove_resource)
 export(resource_names)
 export(resources)
 export(schema)
+export(version)
 export(write_package)
 import(rlang)
 importFrom(readr,problems)

NEWS.md

@@ -2,6 +2,7 @@
 
 ## For users
 
+* New `version()` determines what version of the Data Package standard is used by a Data Package (e.g. `"1.0"`, `"2.0"`, `">=2.0"`). This based on the presence and value of the `$schema` property (#299).
 * `read_resource()` now supports reading from remote zip files, thanks to support in `{vroom}` (1.3.0) (#291).
 * `write_package()` will now print multiple `resource$path` and `resource$schema$missingValues` on multiple lines (#297).
 * `resources()` is soft-deprecated, please use `resource_names()` instead (#282).

R/version.R

@@ -0,0 +1,43 @@
+#' Get Data Package version
+#'
+#' Determines what version of the [Data Package standard](
+#' https://datapackage.org/) is used by a Data Package, based on the
+#' [`$schema`](https://datapackage.org/standard/data-package/#dollar-schema)
+#' property.
+#' Version `"1.0"` is assumed if `$schema` is missing, version `">=2.0"` is
+#' assumed for custom values (e.g. [extensions](
+#' https://datapackage.org/standard/extensions/)).
+#'
+#' @inheritParams read_resource
+#' @returns Data Package version number (e.g. `"1.0"`).
+#' @family version functions
+#' @export
+#' @examples
+#' package <- example_package()
+#' version(package)
+version <- function(package) {
+  dollar_schema <- purrr::pluck(package, "$schema")
+
+  if (is.null(dollar_schema)) {
+    return("1.0") # Assume 1.0 if $schema is undefined
+  }
+  if (!is.character(dollar_schema)) {
+    return(">=2.0") # Assume 2.0 or higher if $schema is present but invalid
+  }
+
+  # Extract version from e.g.
+  # "https://datapackage.org/profiles/<version>/datapackage.json"
+  pattern = "^https://datapackage\\.org/profiles/((?:[0-9A-Za-z]|\\.|-)+)/.*"
+  extracted_version <- sub(
+    pattern,
+    "\\1",
+    dollar_schema,
+    perl = TRUE
+  )
+
+  if (extracted_version == dollar_schema) {
+    return(">=2.0") # Assume 2.0 or higher if $schema is a custom value
+  }
+
+  extracted_version
+}

_pkgdown.yml

@@ -31,4 +31,5 @@ reference:
   - has_concept("accessor functions")
   - has_concept("print functions")
   - has_concept("check functions")
+  - has_concept("version functions")
   - has_concept("sample data")

tests/testthat/test-version.R

@@ -0,0 +1,44 @@
+test_that("version() returns version based on $schema", {
+  p <- create_package()
+
+  # Undefined
+  p$`$schema` <- NULL
+  expect_equal(version(p), "1.0")
+
+  # Defined default
+  p$`$schema` <- "https://datapackage.org/profiles/1.0/datapackage.json"
+  expect_equal(version(p), "1.0")
+
+  # 2.0
+  p$`$schema` <- "https://datapackage.org/profiles/2.0/datapackage.json"
+  expect_equal(version(p), "2.0")
+
+  # Future versions
+  p$`$schema` <- "https://datapackage.org/profiles/2.1/datapackage.json"
+  expect_equal(version(p), "2.1")
+  p$`$schema` <- "https://datapackage.org/profiles/2.2-rc.1/datapackage.json"
+  expect_equal(version(p), "2.2-rc.1")
+  p$`$schema` <- "https://datapackage.org/profiles/3.0/datapackage.json"
+  expect_equal(version(p), "3.0")
+
+  # Custom extensions
+  p$`$schema` <- "https://spatial.datapackage.org/profiles/1.0/datapackage.json"
+  expect_equal(version(p), ">=2.0")
+  p$`$schema` <- "http://rs.tdwg.org/dwc-dp/1.0/dwc-dp-profile.json"
+  expect_equal(version(p), ">=2.0")
+})
+
+test_that("version() returns >=2.0 for invalid $schema", {
+  p <- create_package()
+  p$`$schema` <- list()
+  expect_equal(version(p), ">=2.0")
+  p$`$schema` <- 3.0
+  expect_equal(version(p), ">=2.0")
+})
+
+test_that("version() returns correct version for example packages", {
+  p_1.0 <- example_package(version = "1.0")
+  expect_equal(version(p_1.0), "1.0")
+  p_2.0 <- example_package(version = "2.0")
+  expect_equal(version(p_2.0), "2.0")
+})