add test, delete vignettes

Author: Cedric Qi

pkg/DESCRIPTION

@@ -19,6 +19,5 @@ Imports:
     statmod,
     devtools
 Suggests: 
-    knitr,
-    rmarkdown
-VignetteBuilder: knitr
+    testthat (>= 3.0.0)
+Config/testthat/edition: 3

pkg/tests/testthat.R

@@ -0,0 +1,4 @@
+library(testthat)
+library(FER)
+
+test_check("FER")

pkg/tests/testthat/test-BS.R

@@ -0,0 +1,6 @@
+library(FER)
+
+test_that("Black Scholes Price", {
+  value = BlackScholesPrice(sigma = 0.1, spot = 50, intr = 0.02)
+  expect_equal(value , 1.99, tolerance = 0.1)
+})