examples: add bench_msgpack_json_vs_json2.v to compare the encode/decode performance of msgpack vs json vs x.json2

Author: spytheman

.github/workflows/ci.yml

@@ -32,9 +32,15 @@ jobs:
       - name: Ensure docs is OK
         run: v check-md ~/.vmodules/msgpack/README.md
 
-      - name: Run example with -Wimpure-v
+      - name: Ensure all examples compile with -W
+        run: v -W should-compile-all ~/.vmodules/msgpack/examples/
+
+      - name: Run basic example with -Wimpure-v
         run: v -Wimpure-v crun ~/.vmodules/msgpack/examples/basic.v
 
+      - name: Run bench example
+        run: v run ~/.vmodules/msgpack/examples/bench_msgpack_json_vs_json2.v
+
       - name: Run example with -prod -cstrict -Wimpure-v -cc clang
         run: |
             cd ~/.vmodules/msgpack

examples/bench_msgpack_json_vs_json2.v

@@ -0,0 +1,70 @@
+import os
+import json
+import x.json2
+import msgpack
+import time
+import benchmark
+
+struct Person {
+	name       string
+	age        int
+	created_at time.Time
+}
+
+fn main() {
+	max_iterations := os.getenv_opt('MAX_ITERATIONS') or { '1000' }.int()
+	s := '{"name":"Bilbo Baggins","age":99,"created_at":1670840340}'
+	mut b := benchmark.start()
+
+	for _ in 0 .. max_iterations {
+		p := json2.decode[Person](s)!
+		if p.age != 99 {
+			println('error: ${p}')
+		}
+	}
+	b.measure('json2.decode')
+
+	for _ in 0 .. max_iterations {
+		p := json.decode(Person, s)!
+		if p.age != 99 {
+			println('error: ${p}')
+		}
+	}
+	b.measure('json.decode')
+
+	// encoding measurements:
+	p := json.decode(Person, s)!
+
+	for _ in 0 .. max_iterations {
+		es := json2.encode(p)
+		if es[0] != `{` {
+			println('json2.encode error: ${es}')
+		}
+	}
+	b.measure('json2.encode')
+
+	for _ in 0 .. max_iterations {
+		es := json.encode(p)
+		if es[0] != `{` {
+			println('json.encode error: ${es}')
+		}
+	}
+	b.measure('json.encode')
+
+	for _ in 0 .. max_iterations {
+		es := msgpack.encode[Person](p)
+		if p.age != 99 {
+			println('error: ${es}')
+		}
+	}
+	b.measure('msgpack.encode')
+
+	encoded := msgpack.encode[Person](p)
+	dump(encoded#[0..10])
+	mut decoder := msgpack.new_decoder()
+	for _ in 0 .. max_iterations {
+		// TODO: investigate why decoder.decode does not return a result at all :-|
+		decoder.decode(encoded)!
+	}
+	b.measure('msgpack.decode')
+}