Disallow TimeSpan.Zero in rate limiters

src/libraries/System.Threading.RateLimiting/src/System/Threading/RateLimiting/FixedWindowRateLimiter.cs

@@ -59,9 +59,9 @@ public FixedWindowRateLimiter(FixedWindowRateLimiterOptions options)
             {
                 throw new ArgumentException($"{nameof(options.QueueLimit)} must be set to a value greater than or equal to 0.", nameof(options));
             }
-            if (options.Window < TimeSpan.Zero)
+            if (options.Window <= TimeSpan.Zero)
             {
-                throw new ArgumentException($"{nameof(options.Window)} must be set to a value greater than or equal to TimeSpan.Zero.", nameof(options));
+                throw new ArgumentException($"{nameof(options.Window)} must be set to a value greater than TimeSpan.Zero.", nameof(options));
             }
 
             _options = new FixedWindowRateLimiterOptions

src/libraries/System.Threading.RateLimiting/src/System/Threading/RateLimiting/FixedWindowRateLimiterOptions.cs

@@ -10,9 +10,8 @@ public sealed class FixedWindowRateLimiterOptions
     {
         /// <summary>
         /// Specifies the time window that takes in the requests.
-        /// Must be set to a value >= <see cref="TimeSpan.Zero" /> by the time these options are passed to the constructor of <see cref="FixedWindowRateLimiter"/>.
+        /// Must be set to a value greater than <see cref="TimeSpan.Zero" /> by the time these options are passed to the constructor of <see cref="FixedWindowRateLimiter"/>.
         /// </summary>
-        /// <remarks><see cref="TimeSpan.Zero"/> means the limiter will never replenish.</remarks>
         public TimeSpan Window { get; set; } = TimeSpan.Zero;
 
         /// <summary>

src/libraries/System.Threading.RateLimiting/src/System/Threading/RateLimiting/SlidingWindowRateLimiter.cs

@@ -63,9 +63,9 @@ public SlidingWindowRateLimiter(SlidingWindowRateLimiterOptions options)
             {
                 throw new ArgumentException($"{nameof(options.QueueLimit)} must be set to a value greater than or equal to 0.", nameof(options));
             }
-            if (options.Window < TimeSpan.Zero)
+            if (options.Window <= TimeSpan.Zero)
             {
-                throw new ArgumentException($"{nameof(options.Window)} must be set to a value greater than or equal to TimeSpan.Zero.", nameof(options));
+                throw new ArgumentException($"{nameof(options.Window)} must be set to a value greater than TimeSpan.Zero.", nameof(options));
             }
 
             _options = new SlidingWindowRateLimiterOptions

src/libraries/System.Threading.RateLimiting/src/System/Threading/RateLimiting/SlidingWindowRateLimiterOptions.cs

@@ -10,9 +10,8 @@ public sealed class SlidingWindowRateLimiterOptions
     {
         /// <summary>
         /// Specifies the minimum period between replenishments.
-        /// Must be set to a value >= <see cref="TimeSpan.Zero" /> by the time these options are passed to the constructor of <see cref="SlidingWindowRateLimiter"/>.
+        /// Must be set to a value greater than <see cref="TimeSpan.Zero" /> by the time these options are passed to the constructor of <see cref="SlidingWindowRateLimiter"/>.
         /// </summary>
-        /// <remarks><see cref="TimeSpan.Zero"/> means the limiter will never replenish.</remarks>
         public TimeSpan Window { get; set; } = TimeSpan.Zero;
 
         /// <summary>

src/libraries/System.Threading.RateLimiting/src/System/Threading/RateLimiting/TokenBucketRateLimiter.cs

@@ -61,9 +61,9 @@ public TokenBucketRateLimiter(TokenBucketRateLimiterOptions options)
             {
                 throw new ArgumentException($"{nameof(options.QueueLimit)} must be set to a value greater than or equal to 0.", nameof(options));
             }
-            if (options.ReplenishmentPeriod < TimeSpan.Zero)
+            if (options.ReplenishmentPeriod <= TimeSpan.Zero)
             {
-                throw new ArgumentException($"{nameof(options.ReplenishmentPeriod)} must be set to a value greater than or equal to TimeSpan.Zero.", nameof(options));
+                throw new ArgumentException($"{nameof(options.ReplenishmentPeriod)} must be set to a value greater than TimeSpan.Zero.", nameof(options));
             }
 
             _options = new TokenBucketRateLimiterOptions

src/libraries/System.Threading.RateLimiting/src/System/Threading/RateLimiting/TokenBucketRateLimiterOptions.cs

@@ -10,9 +10,8 @@ public sealed class TokenBucketRateLimiterOptions
     {
         /// <summary>
         /// Specifies the minimum period between replenishments.
-        /// Must be set to a value >= <see cref="TimeSpan.Zero" /> by the time these options are passed to the constructor of <see cref="TokenBucketRateLimiter"/>.
+        /// Must be set to a value greater than <see cref="TimeSpan.Zero" /> by the time these options are passed to the constructor of <see cref="TokenBucketRateLimiter"/>.
         /// </summary>
-        /// <remarks><see cref="TimeSpan.Zero"/> means the limiter will never replenish.</remarks>
         public TimeSpan ReplenishmentPeriod { get; set; } = TimeSpan.Zero;
 
         /// <summary>

src/libraries/System.Threading.RateLimiting/tests/FixedWindowRateLimiterTests.cs

@@ -71,6 +71,15 @@ public override void InvalidOptionsThrows()
                     Window = TimeSpan.FromMinutes(-2),
                     AutoReplenishment = false,
                 }));
+            Assert.Throws<ArgumentException>(
+                () => new FixedWindowRateLimiter(new FixedWindowRateLimiterOptions
+                {
+                    PermitLimit = 1,
+                    QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
+                    QueueLimit = 1,
+                    Window = TimeSpan.Zero,
+                    AutoReplenishment = false,
+                }));
         }
 
         [Fact]

src/libraries/System.Threading.RateLimiting/tests/SlidingWindowRateLimiterTests.cs

@@ -87,6 +87,16 @@ public override void InvalidOptionsThrows()
                     SegmentsPerWindow = 1,
                     AutoReplenishment = false
                 }));
+            Assert.Throws<ArgumentException>(
+                () => new SlidingWindowRateLimiter(new SlidingWindowRateLimiterOptions
+                {
+                    PermitLimit = 1,
+                    QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
+                    QueueLimit = 1,
+                    Window = TimeSpan.Zero,
+                    SegmentsPerWindow = 1,
+                    AutoReplenishment = false
+                }));
         }
 
         [Fact]

src/libraries/System.Threading.RateLimiting/tests/TokenBucketRateLimiterTests.cs

@@ -87,6 +87,16 @@ public override void InvalidOptionsThrows()
                     TokensPerPeriod = 1,
                     AutoReplenishment = false
                 }));
+            Assert.Throws<ArgumentException>(
+                () => new TokenBucketRateLimiter(new TokenBucketRateLimiterOptions
+                {
+                    TokenLimit = 1,
+                    QueueProcessingOrder = QueueProcessingOrder.NewestFirst,
+                    QueueLimit = 1,
+                    ReplenishmentPeriod = TimeSpan.Zero,
+                    TokensPerPeriod = 1,
+                    AutoReplenishment = false
+                }));
         }
 
         [Fact]