Duplicate Column Names when Calling `ggraph()`

[billdenney]

This appears to be distinct from #138 (because I just installed the github versions of ggraph and tidygraph).

I get this error:

Error: `data` must be uniquely named but has duplicate columns
Call `rlang::last_error()` to see a backtrace

When I try to generate this graph.

library(tidygraph)
library(ggraph)
library(tidyverse)

model_diagram <-
  create_empty(n=0, directed=TRUE) %>%
  bind_nodes(
    data.frame(new=c("D"=1, "PK"=2, "PK_elim"=3, "M"=4, "M_in"=5, "M_in_node"=6, "M_out"=7), stringsAsFactors=FALSE)
  ) %>%
  bind_edges(
    data.frame(
      from=c("D"=1 , "PK"=2     , "PK"=2       , "M_in"=5     , "M_in_node"=6, "M"=4),
      to=  c("PK"=2, "PK_elim"=3, "M_in_node"=6, "M_in_node"=6, "M"=4        , "M_out"=7),
      stringsAsFactors=FALSE
    )
  )

model_layout <-
  create_layout(
    graph=model_diagram,
    layout="manual",
    x=c(1, 1, 1, 2, 2, 2, 2),
    y=-c(1, 2, 3, 1, 2, 3, 4)
  )

ggraph(
  graph=model_diagram,
  layout=model_layout
) +
  geom_edge_link() +
  geom_node_point()

[thommohr]

Dear Developers,

today I tried the example with the newst ggraph version. It still persists.

[thomasp85]

if you are using a precalculated layout this should just be passed directly as the graph argument:

this works:

ggraph(
  graph=model_layout
) +
  geom_edge_link() +
  geom_node_point()

I agree the error is non-sensical and I'll try to fix that part

[billdenney]

Is it possible to simplify the fact that the layout should be passed as the graph argument? The two things that occur to me are:

• Give a warning and switch the precalculated layout to the graph argument (seems easier for the user)
• Give an error indicating that the user should make the switch of the layout argument to the graph argument.

[thomasp85]

There will be a warning