Refactor exception handling across multiple test files

Refactored exception handling in tests across multiple modules, replacing previous implementations with the centralized and enhanced `is-exception?` macro. This macro captures the exception type and message and eliminates repeated code, enhancing code cleanliness and maintainability.

src/sicp/chapter_2/part_1/ex_2_10.clj

@@ -12,7 +12,7 @@
   (if (< (* (m/lower-bound interval-2)
             (m/upper-bound interval-2))
          0)
-    (m/error "interval-2 is spanning zero")
+    (m/error "Interval-2 is spanning zero")
     (m/mul-interval
       interval-1
       (m/make-interval (/ 1.0 (m/lower-bound interval-2))

src/sicp/misc.clj

@@ -1,4 +1,6 @@
-(ns sicp.misc)
+(ns sicp.misc
+  (:require
+    [clojure.test :refer [is]]))
 
 (comment "Chapter #1 The Elements of Programming -------------------------------------------------")
 
@@ -191,3 +193,19 @@
   (if (empty? list1)
     (if (empty? list2) '() list2)
     (cons (first list1) (append (rest list1) list2))))
+
+(defmacro is-exception?
+  [test-code & [expected-message exception-type]]
+  `(try
+     ~test-code
+     (if (nil? ~exception-type)
+       (is false "Execution of the code expects any type of exception to be thrown")
+       (is false (str "Expected exception " ~exception-type " was not thrown")))
+     (catch Exception e#
+       (when ~exception-type
+         (is (= (class e#) ~exception-type)
+             (str "Expected exception type " ~exception-type ", but got " (class e#))))
+       (when ~expected-message
+         (is (= (.getMessage e#) ~expected-message)
+             (str "Expected message: " ~expected-message ", but got: " (.getMessage e#))))
+       true)))

test/sicp/chapter_1/part_3/book_1_3_test.clj

@@ -87,10 +87,9 @@
   (is (= 6.103515625E-5 (b13/half-interval-method m/cube -1.0 9.0)))
   (is (= 3.14111328125 (b13/half-interval-method #(Math/sin %) 2.0 4.0)))
   (is (= 1.89306640625 (b13/half-interval-method #(- (m/cube %) (* 2 %) 3) 1.0 2.0)))
-  (is (thrown-with-msg?
-        Exception
-        #"Values are not of opposite sign 1 1"
-        (b13/half-interval-method m/cube 1 1))))
+  (is (m/is-exception?
+        (b13/half-interval-method m/cube 1 1)
+        "Values are not of opposite sign 1 1")))
 
 (deftest fixed-point-test
   (is (= 0.7390822985224024 (b13/fixed-point #(Math/cos %) -1.0)))

test/sicp/chapter_2/part_1/book_2_1_test.clj

@@ -1,7 +1,8 @@
 (ns sicp.chapter-2.part-1.book-2-1-test
   (:require
     [clojure.test :refer [deftest is]]
-    [sicp.chapter-2.part-1.book-2-1 :as b21]))
+    [sicp.chapter-2.part-1.book-2-1 :as b21]
+    [sicp.misc :as m]))
 
 (comment "2 Building Abstractions with Data ------------------------------------------------------")
 
@@ -76,7 +77,6 @@
 (deftest pair-alt-test
   (is (= 1 (b21/car-alt (b21/pair-alt 1 2))))
   (is (= 2 (b21/cdr-alt (b21/pair-alt 1 2))))
-  (is (thrown-with-msg?
-        Exception
-        #"Argument not 0 or 1: CONS"
-        ((b21/pair-alt 1 2) 2))))
+  (is (m/is-exception?
+        ((b21/pair-alt 1 2) 2)
+        "Argument not 0 or 1: CONS")))

test/sicp/chapter_2/part_1/ex_2_10_test.clj

@@ -6,11 +6,7 @@
 
 (deftest div-interval-test
   (is (= [-1.5 -0.5]
-         (div-interval (m/make-interval 10 15) (m/make-interval -10 -20)))))
-
-(deftest exception-with-message-test
-  (try
-    (div-interval (m/make-interval 1 2) (m/make-interval -1 2))
-    (is false "Exception not thrown")
-    (catch Exception e
-      (is (= (.getMessage e) "interval-2 is spanning zero")))))
+         (div-interval (m/make-interval 10 15) (m/make-interval -10 -20))))
+  (is (m/is-exception?
+        (div-interval (m/make-interval 1 2) (m/make-interval -1 2))
+        "Interval-2 is spanning zero")))

test/sicp/chapter_2/part_3/ex_2_68_test.clj

@@ -2,26 +2,17 @@
   (:require
     [clojure.test :refer [deftest is]]
     [sicp.chapter-2.part-3.book-2-3 :as b23]
-    [sicp.chapter-2.part-3.ex-2-68 :refer [encode encode-symbol]]))
+    [sicp.chapter-2.part-3.ex-2-68 :refer [encode encode-symbol]]
+    [sicp.misc :as m]))
 
 (deftest encode-symbol-test
   (is (= b23/huffman-A (encode-symbol :A b23/huffman-tree)))
   (is (= b23/huffman-B (encode-symbol :B b23/huffman-tree)))
   (is (= b23/huffman-C (encode-symbol :C b23/huffman-tree)))
-  (is (= b23/huffman-D (encode-symbol :D b23/huffman-tree))))
-
-(deftest encode-symbol-exception-test
-  (is (thrown-with-msg?
-        Exception
-        #"Symbol not found in tree :Z"
-        (encode-symbol :Z b23/huffman-tree))))
-
-(deftest encode-exception-test
-  (try
-    (encode-symbol :Z b23/huffman-tree)
-    (is false "Exception not thrown")
-    (catch Exception e
-      (is (= (.getMessage e) "Symbol not found in tree :Z")))))
+  (is (= b23/huffman-D (encode-symbol :D b23/huffman-tree)))
+  (is (m/is-exception?
+        (encode-symbol :Z b23/huffman-tree)
+        "Symbol not found in tree :Z")))
 
 (deftest encode-test
   (is (= '(0                                                ; A

test/sicp/chapter_2/part_4/book_2_4_test.clj

@@ -1,7 +1,8 @@
 (ns sicp.chapter-2.part-4.book-2-4-test
   (:require
     [clojure.test :refer [deftest is]]
-    [sicp.chapter-2.part-4.book-2-4 :as b24]))
+    [sicp.chapter-2.part-4.book-2-4 :as b24]
+    [sicp.misc :as m]))
 
 (def angle-60 (/ Math/PI 3))
 (def radius 2.0)
@@ -127,4 +128,7 @@
   (is (= x ((b24/make-from-real-imag x y) :real-part)))
   (is (= y ((b24/make-from-real-imag x y) :imag-part)))
   (is (= radius ((b24/make-from-real-imag x y) :magnitude)))
-  (is (= angle-60 ((b24/make-from-real-imag x y) :angle))))
+  (is (= angle-60 ((b24/make-from-real-imag x y) :angle)))
+  (is (m/is-exception?
+        ((b24/make-from-real-imag x y) :undefined)
+        "Unknown op: MAKE-FROM-REAL-IMAG :undefined")))

test/sicp/misc_test.clj

@@ -6,10 +6,9 @@
 (comment "Chapter #1 The Elements of Programming -------------------------------------------------")
 
 (deftest error-test
-  (try
-    (m/error "123")
-    (catch Exception e
-      (is (= (.getMessage e) "123")))))
+  (is (m/is-exception? (m/error "123")))
+  (is (m/is-exception? (m/error "123") "123"))
+  (is (m/is-exception? (m/error "123") "123" Exception)))
 
 (deftest square-test
   (is (= 4 (m/square 2)))