Phase 1: PS7 correctness fixes

PSGraph/Public/Export-PSGraph.ps1

@@ -30,7 +30,6 @@ function Export-PSGraph
         It checks the piped data for file paths. If it cannot find a file, it assumes it is graph data.
         This may give unexpected errors when the file does not exist.
     #>
-    [Diagnostics.CodeAnalysis.SuppressMessageAttribute("PSAvoidUsingInvokeExpression", "")]
     [cmdletbinding()]
     param(
         # The GraphViz file to process or contents of the graph in Dot notation
@@ -89,18 +88,34 @@ function Export-PSGraph
     {
         try
         {
-            # Use Resolve-Path to test all passed paths
-            # Select only items with 'dot' BaseName and use first one
-            $graphViz = Resolve-Path -path $GraphVizPath -ErrorAction SilentlyContinue | Get-Item | Where-Object BaseName -eq 'dot' | Select-Object -First 1
+            $graphViz = $null
+
+            # Unless the caller explicitly pinned a path, prefer a cross-platform
+            # PATH lookup (works regardless of install location/OS).
+            if ( -Not $PSBoundParameters.ContainsKey('GraphVizPath') )
+            {
+                $graphViz = Get-Command -Name 'dot' -CommandType Application -ErrorAction SilentlyContinue | Select-Object -First 1
+            }
+
+            if ( $null -eq $graphViz )
+            {
+                # Use Resolve-Path to test all passed/default paths
+                # Select only items with 'dot' BaseName and use first one
+                $graphViz = Resolve-Path -path $GraphVizPath -ErrorAction SilentlyContinue | Get-Item | Where-Object BaseName -eq 'dot' | Select-Object -First 1
+            }
 
             if ( $null -eq $graphViz )
             {
                 $GraphvizPathString = $GraphVizPath -Join " or "
-                throw "Could not find GraphViz installed on this system. Please run 'Install-GraphViz' to install the needed binaries and libraries. This module just a wrapper around GraphViz and is looking for it in the following paths: $($GraphvizPathString). Optionally pass a path to your dot.exe file with the GraphVizPath parameter"
+                throw "Could not find GraphViz installed on this system. Please run 'Install-GraphViz' to install the needed binaries and libraries. This module looked for a 'dot' executable on PATH and in the following paths: $($GraphvizPathString). Optionally pass a path to your dot.exe file with the GraphVizPath parameter"
             }
 
             $useStandardInput = $false
             $standardInput = New-Object System.Text.StringBuilder
+
+            # Pipe DOT source to graphviz as UTF-8 without a BOM, regardless of the
+            # caller's ambient $OutputEncoding (a BOM here breaks dot's parser).
+            $OutputEncoding = [System.Text.UTF8Encoding]::new($false)
         }
         catch
         {
@@ -195,7 +210,7 @@ function Export-PSGraph
                 {
                     # Launches image with default viewer as decided by explorer
                     Write-Verbose "Launching $($PSBoundParameters["DestinationPath"])"
-                    Invoke-Expression $PSBoundParameters["DestinationPath"]
+                    Invoke-Item -Path $PSBoundParameters["DestinationPath"]
                 }
 
                 Get-ChildItem $PSBoundParameters["DestinationPath"]

PSGraph/Public/Graph.ps1

@@ -91,7 +91,10 @@ function Graph
             if ($Type -eq 'digraph')
             {
                 $script:indent = 0
-                $Attributes.compound = 'true'
+                if (-not $Attributes.ContainsKey('compound'))
+                {
+                    $Attributes.compound = 'true'
+                }
                 $script:SubGraphList = @{}
             }
 

Tests/Export-PSGraph.Tests.ps1

@@ -30,4 +30,68 @@ Describe "$ModuleName Export-PSGraph" -Tag graphviz {
             "$path.png" | Should Exist
         }
     }
+
+    Context "#110 ShowGraph and destination path with spaces" {
+
+        It "Exports to a destination path containing spaces without throwing" {
+            $dir = Join-Path $testdrive "spaced dir"
+            New-Item -ItemType Directory -Path $dir -Force | Out-Null
+            $path = Join-Path $dir "spaced graph.png"
+
+            { Export-PSGraph -Source $dot -DestinationPath $path -ErrorAction Stop } | Should Not Throw
+
+            $path | Should Exist
+        }
+
+        It "-ShowGraph launches a destination path containing spaces without throwing" {
+            $dir = Join-Path $testdrive "spaced dir 2"
+            New-Item -ItemType Directory -Path $dir -Force | Out-Null
+            $path = Join-Path $dir "spaced graph.png"
+
+            { Export-PSGraph -Source $dot -DestinationPath $path -ShowGraph -ErrorAction Stop } | Should Not Throw
+
+            $path | Should Exist
+        }
+    }
+
+    Context "#97 BOM in generated DOT breaks dot's parser" {
+
+        AfterEach {
+            $OutputEncoding = [System.Text.UTF8Encoding]::new($false)
+        }
+
+        It "Exports successfully even when the caller's `$OutputEncoding would inject a BOM" {
+            $OutputEncoding = [System.Text.UTF8Encoding]::new($true)
+            $path = "$testdrive\bom.dot"
+
+            { Export-PSGraph -Source $dot -DestinationPath $path -OutputFormat dot -ErrorAction Stop } | Should Not Throw
+
+            $bytes = [System.IO.File]::ReadAllBytes($path)
+            ($bytes[0] -eq 0xEF -and $bytes[1] -eq 0xBB -and $bytes[2] -eq 0xBF) | Should Be $false
+        }
+    }
+
+    Context "#104 Non-ASCII characters in labels" {
+
+        It "Round-trips accented/non-ASCII labels through dot without garbling" {
+            $accented = graph g { node cafe @{label = 'héllo wörld'} }
+            $path = "$testdrive\accented.dot"
+
+            Export-PSGraph -Source $accented -DestinationPath $path -OutputFormat dot
+
+            $text = [System.IO.File]::ReadAllText($path, [System.Text.Encoding]::UTF8)
+            $text | Should Match 'héllo wörld'
+        }
+    }
+
+    Context "#75 #88 #85 Graphviz path detection" {
+
+        It "Finds dot via PATH when -GraphVizPath is not specified" {
+            { Export-PSGraph -Source $dot -DestinationPath "$testdrive\pathlookup.png" -ErrorAction Stop } | Should Not Throw
+        }
+
+        It "Honors an explicitly-supplied -GraphVizPath instead of silently falling back to PATH" {
+            { Export-PSGraph -Source $dot -DestinationPath "$testdrive\badpath.png" -GraphVizPath 'C:\does\not\exist\dot.exe' -ErrorAction Stop } | Should Throw
+        }
+    }
 }

Tests/Regression.Tests.ps1

@@ -113,10 +113,46 @@ Describe "Regression tests for Github issues" -Tag Build {
     Context "Sequential edges require parameter name for attributes #40" {
 
         It "#40 correctly handles the positional attributes" {
-            $graph = Graph g {      
-                Edge a, b, c, d, a @{label = 'to'}            
+            $graph = Graph g {
+                Edge a, b, c, d, a @{label = 'to'}
             }
             $graph | Out-String | Should Not Match 'System.Collections.Hashtable'
         }
     }
+
+    Context "#98 Setting compound=false fails" {
+
+        It "#98 an explicit compound=`$false attribute is not overridden" {
+            $graph = Graph g -Attributes @{compound = $false} {} | Out-String
+            $graph | Should Match 'compound="False"'
+            $graph | Should Not Match 'compound="true"'
+        }
+
+        It "#98 compound still defaults to true when not specified" {
+            $graph = Graph g {} | Out-String
+            $graph | Should Match 'compound="true"'
+        }
+    }
+
+    Context "#66 SubGraph example from help/docs" {
+
+        It "#66 unnamed subgraph binds with -Attributes and -ScriptBlock passed by name" {
+            {
+                graph {
+                    subgraph -Attributes @{label = 'DMZ'} -ScriptBlock {
+                        node web1, web2
+                    }
+                }
+            } | Should Not Throw
+        }
+
+        It "#66 unnamed subgraph with named parameters applies the attributes" {
+            $graph = graph {
+                subgraph -Attributes @{label = 'DMZ'} -ScriptBlock {
+                    node web1
+                }
+            } | Out-String
+            $graph | Should Match 'label="DMZ"'
+        }
+    }
 }

docs/Command-SubGraph.md

@@ -3,7 +3,7 @@
 This allows you to define a graph within the graph. This will group those objects together in some engines.
 
      graph {
-        subgraph -Attributes @{label='DMZ'} {
+        subgraph -Attributes @{label='DMZ'} -ScriptBlock {
             node web1,web2,reports
             edge report -To web1,web2
         }