Some code-cleanups by FSharpLint

src/FSharp.Data.DesignTime/CommonProviderImplementation/AssemblyResolver.fs

@@ -20,7 +20,7 @@ let init () =
     if not initialized then
         initialized <- true
 
-        if WebRequest.DefaultWebProxy <> null then
+        if not (isNull WebRequest.DefaultWebProxy) then
             WebRequest.DefaultWebProxy.Credentials <- CredentialCache.DefaultNetworkCredentials
 
         ProvidedTypes.ProvidedTypeDefinition.Logger

src/FSharp.Data.DesignTime/CommonProviderImplementation/Helpers.fs

@@ -296,7 +296,7 @@ module internal ProviderHelpers =
                         while max > 0 do
                             let line = reader.ReadLine()
 
-                            if line = null then
+                            if isNull line then
                                 max <- 0
                             else
                                 line |> sb.AppendLine |> ignore

src/FSharp.Data.DesignTime/CommonProviderImplementation/QuotationBuilder.fs

@@ -1,4 +1,4 @@
-// Copyright 2011-2015, Tomas Petricek (http://tomasp.net), Gustavo Guerra (http://functionalflow.co.uk), and other contributors
+// Copyright 2011-2015, Tomas Petricek (http://tomasp.net), Gustavo Guerra (http://functionalflow.co.uk), and other contributors
 // Licensed under the Apache License, Version 2.0, see LICENSE.md in this project
 //
 // Utilities for building F# quotations without quotation literals
@@ -61,7 +61,7 @@ let (?) (typ: Type) (operation: string) (args1: 'T) (args2: 'U) : Expr =
         match typ.GetMember(operation, MemberTypes.All, flags) with
         | [| :? MethodInfo as mi |] ->
             let mi =
-                if tyargs = [] then
+                if List.isEmpty tyargs then
                     mi
                 else
                     mi.MakeGenericMethod(tyargs |> Array.ofList)

src/FSharp.Data.Html.Core/HtmlOperations.fs

@@ -326,7 +326,7 @@ module HtmlNode =
         let rec selectElements' level acc source =
 
             // if we already have an empty list, terminate early
-            if acc = [] then
+            if List.isEmpty acc then
                 []
             else
 

src/FSharp.Data.Html.Core/HtmlRuntime.fs

@@ -267,10 +267,7 @@ module HtmlRuntime =
 
             let rowLengths =
                 cells
-                |> List.map (fun row ->
-                    row
-                    |> List.map (fun (_, col) -> colSpan col)
-                    |> List.fold (+) 0)
+                |> List.map (fun row -> row |> List.sumBy (snd >> colSpan))
 
             let numberOfColumns = List.max rowLengths
 

src/FSharp.Data.Http/Http.fs

@@ -1620,7 +1620,7 @@ module internal HttpHelpers =
 
     let runningOnMono =
         try
-            System.Type.GetType("Mono.Runtime") <> null
+            not (isNull (System.Type.GetType "Mono.Runtime"))
         with e ->
             false
 
@@ -1637,7 +1637,7 @@ module internal HttpHelpers =
             let remoteStackTraceString =
                 typeof<exn>.GetField ("_remoteStackTraceString", BindingFlags.Instance ||| BindingFlags.NonPublic)
 
-            if remoteStackTraceString <> null then
+            if not (isNull remoteStackTraceString) then
                 remoteStackTraceString.SetValue(e, e.StackTrace + Environment.NewLine)
         with _ ->
             ()
@@ -1651,7 +1651,7 @@ module internal HttpHelpers =
             with
             // If an exception happens, augment the message with the response
             | :? WebException as exn ->
-                if exn.Response = null then reraisePreserveStackTrace exn
+                if isNull exn.Response then reraisePreserveStackTrace exn
 
                 let responseExn =
                     try
@@ -1749,12 +1749,12 @@ module internal HttpHelpers =
             | "pragma" -> req.Headers.[HeaderEnum.Pragma] <- value
             | "range" ->
                 if not (value.StartsWith("bytes=")) then
-                    failwith "Invalid value for the Range header"
+                    failwithf "Invalid value for the Range header (%O)" value
 
                 let bytes = value.Substring("bytes=".Length).Split('-')
 
                 if bytes.Length <> 2 then
-                    failwith "Invalid value for the Range header"
+                    failwithf "Invalid value for the Range header (%O)" bytes
 
                 req.AddRange(int64 bytes.[0], int64 bytes.[1])
             | "proxy-authorization" -> req.Headers.[HeaderEnum.ProxyAuthorization] <- value
@@ -1803,7 +1803,7 @@ module internal HttpHelpers =
                 try
                     return! getResponseAsync req
                 with :? WebException as exc ->
-                    if exc.Response <> null then
+                    if not (isNull exc.Response) then
                         return exc.Response
                     else
                         reraisePreserveStackTrace exc
@@ -2164,7 +2164,7 @@ type Http private () =
                         (defaultArg silentCookieErrors false)
 
                 let contentType =
-                    if resp.ContentType = null then
+                    if isNull resp.ContentType then
                         "application/octet-stream"
                     else
                         resp.ContentType
@@ -2174,7 +2174,7 @@ type Http private () =
                     | :? HttpWebResponse as resp -> int resp.StatusCode, resp.CharacterSet
                     | _ -> 0, ""
 
-                let characterSet = if characterSet = null then "" else characterSet
+                let characterSet = if isNull characterSet then "" else characterSet
 
                 let stream = resp.GetResponseStream()
 

src/FSharp.Data.Json.Core/JsonValue.fs

@@ -300,8 +300,8 @@ type private JsonParser(jsonText: string) =
                     ensure (i + 9 < s.Length)
 
                     let unicodeChar (s: string) =
-                        if s.Length <> 8 then failwith "unicodeChar"
-                        if s.[0..1] <> "00" then failwith "unicodeChar"
+                        if s.Length <> 8 then failwithf "unicodeChar (%O)" s
+                        if s.[0..1] <> "00" then failwithf "unicodeChar (%O)" s
 
                         UnicodeHelper.getUnicodeSurrogatePair
                         <| System.UInt32.Parse(s, NumberStyles.HexNumber)

src/FSharp.Data.Runtime.Utilities/StructuralInference.fs

@@ -411,7 +411,7 @@ let parseUnitOfMeasure (provider: IUnitsOfMeasureProvider) (str: string) =
                 let baseUnitStr = str.[.. str.Length - suffix.Length - 1]
                 let baseUnit = provider.SI baseUnitStr
 
-                if baseUnit = null then
+                if isNull baseUnit then
                     None
                 else
                     baseUnit |> trans provider |> Some
@@ -422,7 +422,7 @@ let parseUnitOfMeasure (provider: IUnitsOfMeasureProvider) (str: string) =
     | Some _ -> unit
     | None ->
         let unit = provider.SI str
-        if unit = null then None else Some unit
+        if isNull unit then None else Some unit
 
 /// The inferred types may be set explicitly via inline schemas.
 /// This table specifies the mapping from (the names that users can use) to (the types used).

src/FSharp.Data.Runtime.Utilities/TextRuntime.fs

@@ -20,7 +20,7 @@ type TextRuntime =
         else
             let mutable cache = TextRuntime.cultureInfoCache
 
-            if cache = null then
+            if isNull cache then
                 cache <- Dictionary<string, CultureInfo>()
                 TextRuntime.cultureInfoCache <- cache
 

src/FSharp.Data.WorldBank.Core/WorldBankRuntime.fs

@@ -73,7 +73,7 @@ module Implementation =
                         Debug.WriteLine(
                             sprintf
                                 "[WorldBank] got text: %s"
-                                (if doc = null then "null"
+                                (if isNull doc then "null"
                                  elif doc.Length > 50 then doc.[0..49] + "..."
                                  else doc)
                         )
@@ -122,7 +122,7 @@ module Implementation =
                               let name = ind?name.AsString().Trim([| '"' |]).Trim()
                               let sourceName = ind?source?value.AsString()
 
-                              if sources = []
+                              if List.isEmpty sources
                                  || sources
                                     |> List.exists (fun source ->
                                         String.Compare(source, sourceName, StringComparison.OrdinalIgnoreCase) = 0) then

src/FSharp.Data.Xml.Core/XmlRuntime.fs

@@ -103,7 +103,7 @@ type XmlRuntime =
 
     static member TryGetAttribute(xml: XmlElement, nameWithNS) =
         let attr = xml.XElement.Attribute(XName.Get(nameWithNS))
-        if attr = null then None else Some attr.Value
+        if isNull attr then None else Some attr.Value
 
     // Operations that obtain children - depending on the inference, we may
     // want to get an array, option (if it may or may not be there) or
@@ -114,12 +114,12 @@ type XmlRuntime =
         let mutable current = value.XElement
 
         for i = 0 to namesWithNS.Length - 2 do
-            if current <> null then
+            if not (isNull current) then
                 current <- current.Element(XName.Get namesWithNS.[i])
 
         let value = current
 
-        if value = null then
+        if isNull value then
             [||]
         else
             [| for c in value.Elements(XName.Get namesWithNS.[namesWithNS.Length - 1]) -> { XElement = c } |]
@@ -193,7 +193,7 @@ type XmlRuntime =
                 match v with
                 | :? XmlElement as v ->
                     let xElement =
-                        if v.XElement.Parent = null then
+                        if isNull v.XElement.Parent then
                             v.XElement
                         else
                             // clone, as element is connected to previous parent
@@ -248,7 +248,7 @@ type XmlRuntime =
             ||> Array.fold (fun parent nameWithNS ->
                 let xname = XName.Get nameWithNS
 
-                if parent = null then
+                if isNull parent then
                     XElement xname
                 else
                     let element =
@@ -257,7 +257,7 @@ type XmlRuntime =
                         else
                             parent.Element(xname)
 
-                    if element = null then
+                    if isNull element then
                         let element = XElement xname
                         parent.Add element
                         element
@@ -271,7 +271,7 @@ type XmlRuntime =
 
             match toXmlContent value with
             | [||] -> ()
-            | [| v |] when v :? string && element.Attribute(xname) = null -> element.SetAttributeValue(xname, v)
+            | [| v |] when v :? string && isNull (element.Attribute xname) -> element.SetAttributeValue(xname, v)
             | _ -> failwithf "Unexpected attribute value: %A" value
 
         let parents = System.Collections.Generic.Dictionary()
@@ -296,7 +296,7 @@ type XmlRuntime =
                              Seq.skip 1 parentNames
                              |> Seq.mapi (fun x i -> x, i))
                             ||> Seq.fold (fun element ((_, nameWithNS) as key) ->
-                                if element.Parent = null then
+                                if isNull element.Parent then
                                     let parent =
                                         match parents.TryGetValue key with
                                         | true, parent -> parent
@@ -313,7 +313,7 @@ type XmlRuntime =
 
                                     element.Parent)
 
-                        if v.Parent = null then element.Add v
+                        if isNull v.Parent then element.Add v
                     | :? string as v ->
                         let child = createElement element nameWithNS
                         child.Value <- v
@@ -345,7 +345,7 @@ module XmlSchema =
 
         let useResolutionFolder (baseUri: System.Uri) =
             resolutionFolder <> ""
-            && (baseUri = null || baseUri.OriginalString = "")
+            && (isNull baseUri || baseUri.OriginalString = "")
 
         let getEncoding xmlText = // peek encoding definition
             let settings = XmlReaderSettings(ConformanceLevel = ConformanceLevel.Fragment)

src/FSharp.Data.Xml.Core/XsdInference.fs

@@ -86,8 +86,10 @@ module XsdParsing =
                 let items = System.Collections.Generic.HashSet()
 
                 let rec collect elm =
-                    if subst.ContainsKey elm then
-                        for x in subst.Item elm do
+                    match subst.TryGetValue elm with
+                    | false, _ -> ()
+                    | true, substVal ->
+                        for x in substVal do
                             if items.Add x then collect x
 
                 collect elm
@@ -98,7 +100,10 @@ module XsdParsing =
                 |> Seq.map (fun x -> x, collectSubst x)
                 |> dict
 
-            fun elm -> if subst'.ContainsKey elm then subst'.Item elm else []
+            fun elm ->
+                match subst'.TryGetValue elm with
+                | true, elVal -> elVal
+                | false, _ -> []
 
 
         let elements =
@@ -303,9 +308,9 @@ module internal XsdInference =
             body :: attrs
         | ComplexContent xsdParticle ->
             let body =
-                if ctx.ContainsKey cty then
-                    ctx.Item cty
-                else
+                match ctx.TryGetValue cty with
+                | true, ctVal -> ctVal
+                | false, _ ->
                     let result =
                         { InferedProperty.Name = ""
                           Type = InferedType.Top }