Return last evaluated from load functions (#984)

Emerged from #979.

Author: mitch-kyle

CHANGELOG.md

@@ -12,12 +12,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Changed
  * Improved on the nREPL server exception messages by matching that of the REPL user friendly format (#968)
  * Types created via `deftype` and `reify` may declare supertypes as abstract (taking precedence over true `abc.ABC` types) and specify their member list using `^:abstract-members` metadata (#942)
+ * Load functions (`load`, `load-file`, `load-reader`, etc) now return the value of the last form evaluated. (#984)
 
 ### Fixed
  * Fixed inconsistent behavior with `basilisp.core/with` when the `body` contains more than one form (#981)
 
 ### Removed
- * Removed `python-dateutil` and `readerwriterlock` as dependencies, switching to standard library components instead (#976) 
+ * Removed `python-dateutil` and `readerwriterlock` as dependencies, switching to standard library components instead (#976)
 
 ### Other
  * Run PyPy CI checks on Github Actions rather than CircleCI (#971)

src/basilisp/core.lpy

@@ -4516,12 +4516,13 @@
                     (.resolve)
                     (python/str))
         ctx (basilisp.lang.compiler.CompilerContext. (or src "<Load Input>"))]
-    (doseq [form (seq (basilisp.lang.reader/read reader
-                                                 *resolver*
-                                                 *data-readers*))]
-      (basilisp.lang.compiler/compile-and-exec-form form
-                                                    ctx
-                                                    *ns*))))
+    (last
+     (for [form (seq (basilisp.lang.reader/read reader
+                                                *resolver*
+                                                *data-readers*))]
+       (basilisp.lang.compiler/compile-and-exec-form form
+                                                     ctx
+                                                     *ns*)))))
 
 (defn load-file
   "Read and evaluate the set of forms contained in the file located at ``path``.
@@ -4581,8 +4582,8 @@
   :lpy:fn:`load-file` (or perhaps :lpy:fn:`load-reader` or :lpy:fn:`load-string`) to
   this function."
   [& paths]
-  (doseq [path (seq paths)]
-    (load-file (str (resolve-load-path path) ".lpy"))))
+  (last (for [path (seq paths)]
+          (load-file (str (resolve-load-path path) ".lpy")))))
 
 (defn ^:inline load-string
   "Read and evaluate the set of forms contained in the string ``s``\\."

tests/basilisp/test_core_fns.lpy

@@ -2302,13 +2302,15 @@
 
 (deftest load-test
 
-  (let [load-dir-test "tests/basilisp/corpus"
-        load-dir-filepath (str load-dir-test "/core_load_1.lpy")]
+  (let [load-dir-test      (str "tests/basilisp/corpus")
+        load-dir-filepath  (str load-dir-test "/core_load_1.lpy")
+        load-dir-otherfile (str load-dir-test "/core_load_2.lpy")]
     (try
       (when (bio/exists? load-dir-test)
         (shutil/rmtree load-dir-test))
       (bio/make-parents load-dir-filepath)
-      (spit load-dir-filepath "(print :core-load-1)")
+      (spit load-dir-filepath  "(print :core-load-1) :core-load-1")
+      (spit load-dir-otherfile "(print :core-load-2) :core-load-2")
 
       (testing "relative load path"
         (let [output (with-out-str (load "corpus/core-load-1"))]
@@ -2322,6 +2324,17 @@
       (testing "non-existent load path"
         (is (thrown? python/FileNotFoundError (load "corpus/core-load-99"))))
 
+      (testing "load multiple files"
+        (let [output (with-out-str (load "corpus/core-load-1"
+                                         "corpus/core-load-2"))]
+          (is (= ":core-load-1:core-load-2" output))))
+
+      (testing "return last form"
+        (let [output (load "corpus/core-load-1")]
+          (is (= :core-load-1 output)))
+        (let [output (load "corpus/core-load-1" "corpus/core-load-2")]
+          (is (= :core-load-2 output))))
+
       (finally
         (when (bio/exists? load-dir-test)
           (shutil/rmtree load-dir-test))))))