Unity custom shader second pass not executing

Question

I have a shader that should do two passes that will render the back one front once. See the shader code below:

Shader "Custom/Geometry/Wireframe"
{
    Properties
    {
        _MainTex ("Texture", 2D) = "white" {}
        [PowerSlider(3.0)]
        _WireframeVal ("Wireframe width", Range(0., 0.34)) = 0.05
        _FrontColor ("Front color", color) = (1., 1., 1., 1.)
        _BackColor ("Back color", color) = (1., 1., 1., 1.)
    }
    SubShader
    {
        Tags { "RenderType"="Opaque" }

        Pass
        {
            Cull Back
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #pragma geometry geom
            #include "UnityCG.cginc"

            struct v2g {
                float4 pos : SV_POSITION;
            };

            struct g2f {
                float4 pos : SV_POSITION;
                float3 bary : TEXCOORD0;
            };

            v2g vert(appdata_base v) {
                v2g o;
                o.pos = UnityObjectToClipPos(v.vertex);
                return o;
            }

            [maxvertexcount(3)]
            void geom(triangle v2g IN[3], inout TriangleStream<g2f> triStream) {
                g2f o;
                o.pos = IN[0].pos;
                o.bary = float3(1., 0., 0.);
                triStream.Append(o);
                o.pos = IN[1].pos;
                o.bary = float3(0., 0., 1.);
                triStream.Append(o);
                o.pos = IN[2].pos;
                o.bary = float3(0., 1., 0.);
                triStream.Append(o);
            }

            float _WireframeVal;
            fixed4 _FrontColor;

            fixed4 frag(g2f i) : SV_Target {
            if(!any(bool3(i.bary.x < _WireframeVal, i.bary.y < _WireframeVal, i.bary.z < _WireframeVal)))
                 discard;

                return _FrontColor;
            }

            ENDCG
        }

        Pass
        {
            Cull Front
            CGPROGRAM
            #pragma vertex vert
            #pragma fragment frag
            #pragma geometry geom
            #include "UnityCG.cginc"

            struct v2g {
                float4 pos : SV_POSITION;
            };

            struct g2f {
                float4 pos : SV_POSITION;
                float3 bary : TEXCOORD0;
            };

            v2g vert(appdata_base v) {
                v2g o;
                o.pos = UnityObjectToClipPos(v.vertex);
                return o;
            }

            [maxvertexcount(3)]
            void geom(triangle v2g IN[3], inout TriangleStream<g2f> triStream) {
                g2f o;
                o.pos = IN[0].pos;
                o.bary = float3(1., 0., 0.);
                triStream.Append(o);
                o.pos = IN[1].pos;
                o.bary = float3(0., 0., 1.);
                triStream.Append(o);
                o.pos = IN[2].pos;
                o.bary = float3(0., 1., 0.);
                triStream.Append(o);
            }

            float _WireframeVal;
            fixed4 _BackColor;

            fixed4 frag(g2f i) : SV_Target {
            if(!any(bool3(i.bary.x < _WireframeVal, i.bary.y < _WireframeVal, i.bary.z < _WireframeVal)))
                 discard;

                return _BackColor;
            }

            ENDCG
        }
    }
}

But the problem i am having is the fact that the second pass in the code is never executing. Because when i set the color for the back -pass That color never becomes visible in the on the mesh the shader (material) is applied to.

Also if i swap the passes so that the back-pass comes before the front-pass the opposite problem occurs.

EDIT
See here a picture of the front of the mesh with the material applied and a picture from the back of the same mesh with material:
Front:

Back:

This is my very first time trying to make such a shader so all help is very much appreaciated!

Answer 1

remove this bracket

Shader "Custom/Geometry/Wireframe"

{<<<<<<<<<<<<
    Properties
    {

this made it work for me

unfortunately there is no auto complete for shaders, so its easy to miss errors like this, but your code gave me the following errors in the editor:

Parse error: syntax error unexpected '{' 3 (extra bracket on line three)

shader is not supported on this gpu ( caused by syntax error)

removing that bracket clears up the problem!

Shader "Custom/NewSurfaceShader" 
{


        Properties
        {
            _MainTex("Texture", 2D) = "white" {}
            [PowerSlider(3.0)]
            _WireframeVal("Wireframe width", Range(0., 0.34)) = 0.05
            _FrontColor("Front color", color) = (1., 1., 1., 1.)
            _BackColor("Back color", color) = (1., 1., 1., 1.)
        }
            SubShader
            {
                Tags { "RenderType" = "Opaque" }

                Pass
                {
                    Cull Back
                    CGPROGRAM
                    #pragma vertex vert
                    #pragma fragment frag
                    #pragma geometry geom
                    #include "UnityCG.cginc"

                    struct v2g {
                        float4 pos : SV_POSITION;
                    };

                    struct g2f {
                        float4 pos : SV_POSITION;
                        float3 bary : TEXCOORD0;
                    };

                    v2g vert(appdata_base v) {
                        v2g o;
                        o.pos = UnityObjectToClipPos(v.vertex);
                        return o;
                    }

                    [maxvertexcount(3)]
                    void geom(triangle v2g IN[3], inout TriangleStream<g2f> triStream) {
                        g2f o;
                        o.pos = IN[0].pos;
                        o.bary = float3(1., 0., 0.);
                        triStream.Append(o);
                        o.pos = IN[1].pos;
                        o.bary = float3(0., 0., 1.);
                        triStream.Append(o);
                        o.pos = IN[2].pos;
                        o.bary = float3(0., 1., 0.);
                        triStream.Append(o);
                    }

                    float _WireframeVal;
                    fixed4 _FrontColor;

                    fixed4 frag(g2f i) : SV_Target {
                    if (!any(bool3(i.bary.x < _WireframeVal, i.bary.y < _WireframeVal, i.bary.z < _WireframeVal)))
                         discard;

                        return _FrontColor;
                    }

                    ENDCG
                }

                Pass
                {
                    Cull Front
                    CGPROGRAM
                    #pragma vertex vert
                    #pragma fragment frag
                    #pragma geometry geom
                    #include "UnityCG.cginc"

                    struct v2g {
                        float4 pos : SV_POSITION;
                    };

                    struct g2f {
                        float4 pos : SV_POSITION;
                        float3 bary : TEXCOORD0;
                    };

                    v2g vert(appdata_base v) {
                        v2g o;
                        o.pos = UnityObjectToClipPos(v.vertex);
                        return o;
                    }

                    [maxvertexcount(3)]
                    void geom(triangle v2g IN[3], inout TriangleStream<g2f> triStream) {
                        g2f o;
                        o.pos = IN[0].pos;
                        o.bary = float3(1., 0., 0.);
                        triStream.Append(o);
                        o.pos = IN[1].pos;
                        o.bary = float3(0., 0., 1.);
                        triStream.Append(o);
                        o.pos = IN[2].pos;
                        o.bary = float3(0., 1., 0.);
                        triStream.Append(o);
                    }

                    float _WireframeVal;
                    fixed4 _BackColor;

                    fixed4 frag(g2f i) : SV_Target {
                    if (!any(bool3(i.bary.x < _WireframeVal, i.bary.y < _WireframeVal, i.bary.z < _WireframeVal)))
                         discard;

                        return _BackColor;
                    }

                    ENDCG
                }
            }
    }