fix bug in picking latest julia version

NAMESPACE

@@ -51,6 +51,8 @@ S3method(solve,JuliaObject)
 S3method(t,JuliaObject)
 export("%>J%")
 export("field<-")
+export(.latest_lts_julia_version_from_versions)
+export(.latest_stable_julia_version_from_versions)
 export(JuliaObject)
 export(autowrap)
 export(eng_juliacall)
@@ -69,9 +71,7 @@ export(julia_help)
 export(julia_install_package)
 export(julia_install_package_if_needed)
 export(julia_installed_package)
-export(julia_latest_version)
 export(julia_library)
-export(julia_lts_version)
 export(julia_markdown_setup)
 export(julia_notebook_setup)
 export(julia_pkg_hook)

R/installJulia.R

@@ -15,33 +15,45 @@ julia_default_install_dir <- function(){
 #'
 #' @return A numeric_version object representing the latest stable Julia version.
 #' @export
+.latest_stable_julia_version_from_versions <- function(versions) {
+    stable_versions <- names(Filter(function(v) isTRUE(v$stable), versions))
+    stable_versions <- sub("^v", "", stable_versions)
+    if (length(stable_versions) == 0) {
+        stop("Could not determine latest stable Julia version.")
+    }
+    max(package_version(stable_versions))
+}
+
 julia_latest_version <- function(){
     url <- "https://julialang-s3.julialang.org/bin/versions.json"
     file <- tempfile()
     utils::download.file(url, file)
     versions <- rjson::fromJSON(file=file)
 
-    max(numeric_version(names(Filter(function(v) v$stable, versions))))
+    .latest_stable_julia_version_from_versions(versions)
 }
 
 #' Get the latest Long Term Support (LTS) Julia version.
 #'
 #' @return A numeric_version object representing the latest LTS Julia version.
 #' @export
+.latest_lts_julia_version_from_versions <- function(versions) {
+    lts_versions <- names(Filter(function(v) isTRUE(v$stable) && isTRUE(v$lts), versions))
+    lts_versions <- sub("^v", "", lts_versions)
+    if (length(lts_versions) > 0) {
+        max(package_version(lts_versions))
+    } else {
+        .latest_stable_julia_version_from_versions(versions)
+    }
+}
+
 julia_lts_version <- function(){
     url <- "https://julialang-s3.julialang.org/bin/versions.json"
     file <- tempfile()
     utils::download.file(url, file)
     versions <- rjson::fromJSON(file=file)
 
-    # Find the latest LTS version (currently 1.10.x series)
-    lts_versions <- names(Filter(function(v) v$stable && isTRUE(v$lts), versions))
-    if (length(lts_versions) > 0) {
-        max(numeric_version(lts_versions))
-    } else {
-        # Fallback to latest stable if no LTS is marked
-        julia_latest_version()
-    }
+    .latest_lts_julia_version_from_versions(versions)
 }
 
 

tests/testthat/test_install_julia_versions.R

@@ -0,0 +1,44 @@
+context("Julia version selection")
+
+test_that("latest stable version uses semantic ordering", {
+    versions <- list(
+        "1.9.4" = list(stable = TRUE),
+        "1.12.5" = list(stable = TRUE),
+        "1.12.6-rc1" = list(stable = FALSE)
+    )
+    expect_equal(
+        as.character(JuliaCall:::.latest_stable_julia_version_from_versions(versions)),
+        "1.12.5"
+    )
+})
+
+test_that("latest stable handles v-prefixed versions", {
+    versions <- list(
+        "v1.10.10" = list(stable = TRUE),
+        "v1.12.5" = list(stable = TRUE)
+    )
+    expect_equal(
+        as.character(JuliaCall:::.latest_stable_julia_version_from_versions(versions)),
+        "1.12.5"
+    )
+})
+
+test_that("latest lts prefers lts and falls back to latest stable", {
+    versions_with_lts <- list(
+        "1.12.5" = list(stable = TRUE),
+        "1.10.10" = list(stable = TRUE, lts = TRUE)
+    )
+    expect_equal(
+        as.character(JuliaCall:::.latest_lts_julia_version_from_versions(versions_with_lts)),
+        "1.10.10"
+    )
+
+    versions_without_lts <- list(
+        "1.11.4" = list(stable = TRUE),
+        "1.12.5" = list(stable = TRUE)
+    )
+    expect_equal(
+        as.character(JuliaCall:::.latest_lts_julia_version_from_versions(versions_without_lts)),
+        "1.12.5"
+    )
+})