add modulo (%) infix operator (#88)

vapor · Feb 12, 2021 · a9b2f07 · a9b2f07
1 parent a2784a9
commit a9b2f07
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Showing 4 changed files with 50 additions and 4 deletions.
diff --git a/Sources/LeafKit/Exports.swift b/Sources/LeafKit/Exports.swift
@@ -35,6 +35,7 @@ extension Character {
                  .minus,
                  .star,
                  .forwardSlash,
+                 .percent,
                  .equals,
                  .exclamation,
                  .lessThan,
@@ -101,6 +102,7 @@ extension Character {
     static let minus = "-".first!
     static let star = "*".first!
     static let forwardSlash = "/".first!
+    static let percent = "%".first!
     static let equals = "=".first!
     static let exclamation = "!".first!
     static let lessThan = "<".first!

diff --git a/Sources/LeafKit/LeafLexer/LeafParameterTypes.swift b/Sources/LeafKit/LeafLexer/LeafParameterTypes.swift
@@ -124,7 +124,7 @@ public enum LeafOperator: String, Equatable, CustomStringConvertible, CaseIterab
 
     internal static let precedenceMap: [(check: ((LeafOperator) -> Bool), infixed: Bool)] = [
         (check: { $0 == .not }, infixed: false), // unaryNot
-        (check: { $0 == .multiply || $0 == .divide }, infixed: true), // Mult/Div
+        (check: { $0 == .multiply || $0 == .divide || $0 == .modulo }, infixed: true), // Mult/Div/Mod
         (check: { $0 == .plus || $0 == .minus }, infixed: true), // Plus/Minus
         (check: { $0 == .greater || $0 == .greaterOrEqual }, infixed: true), // >, >=
         (check: { $0 == .lesser || $0 == .lesserOrEqual }, infixed: true), // <, <=
@@ -146,7 +146,7 @@ public enum LeafOperator: String, Equatable, CustomStringConvertible, CaseIterab
                            lesserOrEqual, and, or, plus, minus, divide,
                            multiply, modulo, assignment, nilCoalesce,
                            scopeMember, subOpen],
-        "unavailable"   : [modulo, assignment, nilCoalesce, evaluate, scopeRoot,
+        "unavailable"   : [assignment, nilCoalesce, evaluate, scopeRoot,
                            scopeMember, subOpen, subClose]
     ]
 }

diff --git a/Sources/LeafKit/LeafSerialize/ParameterResolver.swift b/Sources/LeafKit/LeafSerialize/ParameterResolver.swift
@@ -180,9 +180,10 @@ internal struct ParameterResolver {
                 return try multiply(lhs: lhs, rhs: rhs)
             case .divide:
                 return try divide(lhs: lhs, rhs: rhs)
+            case .modulo:
+                return try modulo(lhs: lhs, rhs: rhs)
             case .assignment: throw "Future feature"
             case .nilCoalesce: throw "Future feature"
-            case .modulo: throw "Future feature"
             case .evaluate: throw "Future feature"
             case .scopeRoot: throw "Future feature"
             case .scopeMember: throw "Future feature"
@@ -303,7 +304,30 @@ internal struct ParameterResolver {
                 let l = load()
                 return try divide(lhs: l, rhs: rhs)
             case .data, .array, .string, .dictionary, .bool:
-                throw "unable to multiply this type `\(lhs)`"
+                throw "unable to divide this type `\(lhs)`"
+        }
+    }
+
+    private func modulo(lhs: LeafData, rhs: LeafData) throws -> LeafData {
+        switch lhs.storage {
+            case .optional(_, _): throw "Optional unwrapping not possible yet"
+            case .int(let i):
+                // if either is double, be double
+                if case .double(let d) = rhs.storage {
+                    let product = Double(i).truncatingRemainder(dividingBy: d)
+                    return .double(product)
+                } else {
+                    let rhs = rhs.int ?? 0
+                    return .int(i % rhs)
+                }
+            case .double(let d):
+                let rhs = rhs.double ?? 0
+                return .double(d.truncatingRemainder(dividingBy: rhs))
+            case .lazy(let load, _, _):
+                let l = load()
+                return try modulo(lhs: l, rhs: rhs)
+            case .data, .array, .string, .dictionary, .bool:
+                throw "unable to apply modulo on this type `\(lhs)`"
         }
     }
 

diff --git a/Tests/LeafKitTests/GHTests/VaporLeafKit.swift b/Tests/LeafKitTests/GHTests/VaporLeafKit.swift
@@ -73,4 +73,24 @@ final class GHLeafKitIssuesTest: XCTestCase {
         let page = try! TestRenderer(sources: .singleSource(test)).render(path: "a", context: ["challenges":["","",""]]).wait()
             XCTAssertEqual(page.string, expected)
     }
+
+    /// https://github.com/vapor/leaf-kit/issues/87
+    func testGH87() {
+        do {
+            let template = """
+            #if(2 % 2 == 0):hi#endif #if(0 == 4 % 2):there#endif
+            """
+            let expected = "hi there"
+            try XCTAssertEqual(render(template, ["a": "a"]), expected)
+        }
+
+        // test with double values
+        do {
+            let template = """
+            #if(5.0 % 2.0 == 1.0):hi#endif #if(4.0 % 2.0 == 0.0):there#endif
+            """
+            let expected = "hi there"
+            try XCTAssertEqual(render(template, ["a": "a"]), expected)
+        }
+    }
 }